This is the accessible text file for GAO report number GAO-10-679SP 
entitled 'Aviation Safety during Winter: Icing and Winter Weather-
Related Recommendations That NTSB Has Issued Since 1996 (an E-
Supplement to GAO-10-678)' which was released on July 29, 2010. 

This text file was formatted by the U.S. Government Accountability 
Office (GAO) to be accessible to users with visual impairments, as 
part of a longer term project to improve GAO products' accessibility. 
Every attempt has been made to maintain the structural and data 
integrity of the original printed product. Accessibility features, 
such as text descriptions of tables, consecutively numbered footnotes 
placed at the end of the file, and the text of agency comment letters, 
are provided but may not exactly duplicate the presentation or format 
of the printed version. The portable document format (PDF) file is an 
exact electronic replica of the printed version. We welcome your 
feedback. Please E-mail your comments regarding the contents or 
accessibility features of this document to Webmaster@gao.gov. 

This is a work of the U.S. government and is not subject to copyright 
protection in the United States. It may be reproduced and distributed 
in its entirety without further permission from GAO. Because this work 
may contain copyrighted images or other material, permission from the 
copyright holder may be necessary if you wish to reproduce this 
material separately. 

GAO-10-679SP: 

Aviation Safety during Winter: Icing and Winter Weather-Related 
Recommendations That NTSB Has Issued Since 1996 (an E-Supplement to 
GAO-10-678): 

Introduction: 

Ice formation on aircraft can disrupt the smooth flow of air over the 
wings and prevent the aircraft from taking off or decrease the pilot's 
ability to maintain control of the aircraft. Taxi and landing 
operations can also be risky in winter weather. Despite a variety of 
technologies designed to prevent ice from forming on planes and to 
remove ice that has formed, as well as persistent efforts by the 
Federal Aviation Administration (FAA) and other stakeholders to 
mitigate icing risks, icing remains a serious concern. 

Since 1996, the National Transportation Safety Board (NTSB) has issued 
89 recommendations aimed at reducing risks from in-flight structural 
icing, engine and aircraft component icing, runway condition and 
contamination, ground icing, and winter weather operations. Eighty-two 
of the recommendations were addressed to FAA, four were addressed to 
air carriers, one was addressed to the National Oceanic and 
Atmospheric Administration (NOAA), and one was addressed to the 
National Atmospheric and Space Administration (NASA). This e-
supplement lists icing and winter weather-related recommendations that 
NTSB has issued since 1996, including the number, issue date, close 
data, most-wanted status, and description of each recommendation. 

[End of section] 

Table of Contents: 

Background: 

Table 1: Definitions of NTSB's Recommendation Status Categories: 

Aircraft Icing and Winter Weather-Related NTSB Recommendations Issued 
Since 1996: 

American Eagle Flight #4184: 

Table 2: NTSB recommendations resulting from the crash of American 
Eagle Flight #4184: 

Tower Air Inc. Flight #41: 

Table 3: Recommendations Resulting from the Accident Involving Tower 
Air Inc. Flight #41: 

ValuJet Airlines Flight #558: 

Table 4: Recommendations Resulting from the Accident Involving ValuJet 
Flight #558: 

Comair Airlines Flight #3272: 

Table 5: Recommendations Resulting from the Crash of Comair Airlines 
Flight #3272: 

Reno Air Flight #153: 

Table 6: Recommendations Resulting from the Incident Involving Reno 
Air Flight #153: 

Garuda Indonesia Airlines Flight #421: 

Table 7: Recommendations Resulting from the Accident Involving Garuda 
Indonesia Airlines Flight #4184: 

Spirit Airlines Flight #970: 

Table 8: Recommendations Resulting from the Incident Involving Spirit 
Airlines Flight #970: 

Accidents and Incidents Involving Cessna 208 Series Airplanes: 

Table 9: Recommendations Made to Address Accidents and Incidents 
Involving Cessna 208 Series Airplanes: 

Engine Power Loss in Raytheon Beechjet 400 Series Airplanes: 

Table 10: Recommendations Resulting from Power Loss in Raytheon 
Beechjet 400 Series Airplanes: 

Glo-Air Flight #73: 

Table 11: Recommendations Resulting from the Crash of Glo-Air Flight 
#73: 

Martinair Circuit City Accident in Pueblo, Colorado: 

Table 12: Recommendations Resulting from the Martinair Circuit City 
Crash: 

Midwest Airlines Flight #490: 

Table 13: Recommendations Resulting from the Crash of Midwest Airlines 
Flight #490: 

Southwest Airlines Flight #1248: 

Table 14: Recommendations Resulting from the Southwest Airlines Flight 
#1248 Accident: 

International Cessna 208 Series Aircraft Accidents: 

Table 15: Recommendations Resulting from Two International General 
Aviation Accidents: 

American Eagle Flight #3008: 

Table 16: Recommendations Resulting from the Incident Involving 
American Eagle Flight #3008: 

Delta Connection Flight #6448: 

Table 17: Recommendations Resulting from the Crash of Delta Connection 
Flight #6448: 

Pinnacle Airlines Flight #4712: 

Table 18: Recommendations Resulting from the Accident Involving 
Pinnacle Airlines Flight #4712: 

[End of section] 

Background: 

A safety recommendation originates from NTSB's accident investigation 
reports, safety studies, or special investigations. NTSB tracks a 
safety recommendation from the date of issue until it is closed; 
safety recommendations are closed only by vote of the Safety Board. 
NTSB assigns a status to each recommendation, descriptions of which 
are listed below in table 1. 

Table 1: Definitions of NTSB's Recommendation Status Categories: 

Status category; Closed--exceeds recommended action; 
Definition of status category: Response by recipient indicates action 
on the safety recommendation has been completed. The action taken 
surpasses what the Safety Board envisioned. 

Status category; Closed--acceptable action; 
Definition of status category: Response by the recipient indicates 
action on the safety recommendation has been completed. The action 
complies with the safety recommendation. 

Status category; Closed--acceptable alternate action; 
Definition of status category: Response by the recipient indicates an 
alternate course of action has been completed that meets the objective 
of the safety recommendation. 

Status category; Closed--unacceptable action; 
Definition of status category: Response by recipient expresses 
disagreement with the need outlined in the recommendation. There is no 
further evidence to offer, and the Safety Board concludes that further 
correspondence on, or discussion of, the matter would not change the 
recipient's position. This status can also be used when the time frame 
goals outlined in this order have not been met. 

Status category; Closed--unacceptable action/no response received; 
Definition of status category: No response to the recommendation was 
ever received. 

Status category; Closed--reconsidered; 
Definition of status category: Recipient rejects the safety 
recommendation and supports this rejection with a rationale with which 
the board concurs. Reasons for the "reconsidered" status would include 
situations where the recipient is able to convince the board that the 
proposed action would not be effective or that it might create other 
problems. This status is also assigned when the recipient of a 
recommendation was in compliance before the recommendation was issued 
or when the recipient was incorrectly chosen and cannot perform the 
recommended action. 

Status category; Closed--no longer applicable; 
Definition of status category: The recommended action has been 
overtaken by events. For example, if technology and/or regulatory 
action have eliminated the reason for the recommendation or if a 
company has gone out of business. 

Status category; Closed--superseded; 
Definition of status category: Applied to recommendations held in an 
open status when a new, more appropriate safety recommendation is 
issued that includes the necessary elements of the recommendation to 
be closed. 

Status category; Closed--acceptable/acceptable alternate/unacceptable 
action superseded; 
Definition of status category: Applied to recommendations held in an 
open status when a new, more appropriate safety recommendation is 
issued that includes the necessary elements of the recommendation to 
be closed. The board determines the acceptable/acceptable 
alternate/unacceptable status based on the criteria defined above 
prior to superseding the recommendation. 

Status category; Open--acceptable response; 
Definition of status category: Response by recipient indicates a 
planned action that would comply with the safety recommendation when 
completed. 

Status category; Open--acceptable alternate response; 
Definition of status category: Response by recipient indicates an 
alternate plan or implementation program that would satisfy the 
objective of the safety recommendation when implemented. 

Status category; Open--unacceptable response; 
Definition of status category: Response by recipient expresses 
disagreement with the need outlined in the recommendation or attempts 
to convince the board (unsuccessfully) that an alternative course of 
action is acceptable. The board believes, however, that there is 
enough supporting evidence to ask the recipient to reconsider its 
position. This status can also be used when the board believes that 
action is not being taken in a timely manner. 

Status category; Open--response received; 
Definition of status category: Response has been received from 
recipient, but staff evaluation of the response has not been approved 
by the board members. 

Status category; Open--await response; 
Definition of status category: When a safety recommendation is issued, 
the status "open-await response" is automatically assigned. 

Source: NTSB. 

[End of table] 

Of the 82 recommendations addressed to FAA, NTSB has closed 41 (50 
percent) as implemented, and has classified another 22 (27 percent) as 
FAA having made acceptable progress.[Footnote 1] This combined 77 
percent acceptance rate is similar to the rate for all of NTSB's 
aviation recommendations. Of the 7 recommendations addressed to other 
stakeholders, NTSB closed 6 as implemented and the remaining 
recommendation remains open, with an acceptable response provided by 
the recipient. 

To develop this complete listing of and information on NTSB's icing- 
related recommendations made since 1996, we obtained data from NTSB 
and summarized it in the tables below. A more detailed discussion of 
aviation safety in icing and winter weather operating conditions is 
contained in our report (GAO-10-678). We conducted our review from 
August 2009 to July 2010 in accordance with generally accepted 
government auditing standards. We provided a draft of this e-
supplement to NTSB officials to obtain their comments and incorporated 
their comments where appropriate. 

Aircraft Icing and Winter Weather-Related NTSB Recommendations Issued 
Since 1996: 

American Eagle Flight #4184: 

On October 31, 1994, American Eagle Flight #4184, an Avions de 
Transport Regional model 72-212 (ATR 72), crashed in Roselawn, Ind. 
All 68 passengers and crewmembers were killed. NTSB determined that 
accident was caused by loss of control, which occurred after a ridge 
of ice built up beyond deicing equipment. The aircraft was flying in 
icing conditions beyond its certification criteria. Additionally, NTSB 
found that FAA's requirements did not adequately account for the 
hazards of flight in freezing rain. 

Table 2: Recommendations Resulting from the Crash of American Eagle 
Flight #4184: 

Recommendation number, date issued, and date closed (where 
applicable): A-96-51; Issued 8/15/1996; Closed 4/28/2010; 
Recipient: FAA; 
Summary of recommendation: Revise the criteria used to report icing 
conditions so that it relates to specific types of aircraft and is 
consistent with existing regulations; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-96-52; Issued 8/15/1996; Closed 5/31/2005; 
Recipient: FAA; 
Summary of recommendation: Publish the definition of the phrase "icing 
in precipitation" in the appropriate aeronautical publications, 
emphasizing that the condition may exist both near the ground and at 
altitude; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-96-53; Issued 8/15/1996; Closed 8/20/1997; 
Recipient: FAA; 
Summary of recommendation: Continue to sponsor the development of 
weather forecast production methods that both define specific 
locations of icing conditions and identify icing conditions for a 
specific time frame within a specific area; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-96-54 (Most Wanted recommendation)[A]; Issued 8/15/1996; 
Recipient: FAA; 
Summary of recommendation: Revise aircraft certification criteria to 
reflect research on aircraft ice buildup under various atmospheric 
conditions and changes in aircraft design and use. Also, expand 
aircraft certification criteria to include a wider range of 
atmospheric conditions; 
Status: Open--unacceptable response; Supersedes A-81-116 and A-81-118. 

Recommendation number, date issued, and date closed (where 
applicable): A-96-55; Issued 8/15/1996; Closed 2/16/2000; 
Recipient: FAA; 
Summary of recommendation: Revise icing certification requirements and 
advisory material to specify methods for icing certification testing; 
Status: Closed--acceptable alternate action. 

Recommendation number, date issued, and date closed (where 
applicable): A-96-56; Most Wanted; Issued 8/15/1996; 
Recipient: FAA; 
Summary of recommendation: Revise certification criteria to ensure 
that aircraft are tested for all conditions in which they are 
authorized to operate, or are otherwise shown to be capable of safe 
flight into such conditions. FAA should prohibit operation in 
conditions beyond the capability of an aircraft and flight crews 
should be given the means to determine when they are in such 
conditions; 
Status: Open--unacceptable response. 

Recommendation number, date issued, and date closed (where 
applicable): A-96-57; Issued 8/15/1996; Closed 2/5/2003; 
Recipient: FAA; 
Summary of recommendation: Require aircraft manufacturers to provide 
information to FAA and operators about any known undesirable 
characteristics of flight beyond the protected flight regime; 
Status: Closed--unacceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-96-58; Issued 8/15/1996; 
Recipient: FAA; 
Summary of recommendation: Develop an icing certification test 
procedure to determine the susceptibility of airplanes to control 
anomalies with and without ice on the wing. Revise icing certification 
requirements to include such a test; 
Status: Open--acceptable response. 

Recommendation number, date issued, and date closed (where 
applicable): A-96-59; Issued 8/15/1996; Closed 2/5/2003; 
Recipient: FAA; 
Summary of recommendation: Encourage ATR (a manufacturer of airplanes) 
to test the newly developed stabilization system design changes. When 
design changes show that the stabilization problem has been corrected, 
require these changes on all new and existing ATR airplanes; 
Status: Closed--unacceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-96-60; Issued 8/15/1996; Closed 11/20/2009; 
Recipient: FAA; 
Summary of recommendation: Ensure that regulations governing small 
commercial and noncommercial airplanes are compatible with the 
published definition of severe icing and eliminate the implied 
authorization of flight into severe icing conditions[B]; 
Status: Closed--acceptable alternate action. 

Recommendation number, date issued, and date closed (where 
applicable): A-96-61; Issued 8/15/1996; Closed 8/20/1997; 
Recipient: FAA; 
Summary of recommendation: Require FAA inspectors to ensure that 
training programs for large commercial and small commercial airplane 
operators include information about all icing conditions, including 
freezing rain and freezing drizzle[C]; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-96-65; Issued 8/15/1996; Closed 8/20/1997; 
Recipient: FAA; 
Summary of recommendation: Evaluate the need to prohibit nonessential 
activities in the cockpit for airplanes holding in weather conditions 
such as icing, hail, and thunderstorms; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-96-68; Issued 8/15/1996; Closed 8/20/1997; 
Recipient: FAA; 
Summary of recommendation: Revise an FAA order governing pilot 
reporting of weather information to include freezing drizzle and 
freezing rain and clearly define these conditions in the 
pilot/controller glossary; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-96-69; Issued 8/15/1996; Closed 1/27/2003; 
Recipient: FAA; 
Summary of recommendation: Conduct or sponsor research and development 
of systems which would alert flight crews when the airplane is 
encountering freezing drizzle and freezing rain and accumulating 
resultant ice; 
Status: Closed--acceptable alternate action. 

Recommendation number, date issued, and date closed (where 
applicable): A-96-70; Issued 8/15/1996; Closed 3/20/1997; 
Recipient: NOAA; 
Summary of recommendation: Develop methods to produce weather 
forecasts that define specific locations of atmospheric icing 
conditions and produce forecasts for a specific time frame and 
location; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-96-71; Issued 8/15/1996; Closed 1/30/2001; 
Recipient: American Eagle; 
Summary of recommendation: Require dispatchers to provide flight crews 
with weather information pertinent to the route of flight to aid in 
preflight and in-flight decisions; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-96-72; Issued 8/15/1996; Closed 1/30/2001; 
Recipient: American Eagle; 
Summary of recommendation: Encourage captains to forgo unnecessary 
activity and conversation in the cockpit when an airplane is holding 
in weather conditions such as icing, hail, or thunderstorms; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-96-73; Issued 8/15/1996; Closed 1/30/2001; 
Recipient: American Eagle; 
Summary of recommendation: Audit aircraft flight manuals, flight 
operations manuals, and other published material to eliminate 
conflicts in guidance and procedures; 
Status: Closed--acceptable action. 

Source: NTSB. 

[A] NTSB's Most Wanted list includes important safety recommendations 
identified for special attention and intensive follow-up. NTSB 
established the list in 1990 and annually updates it. 

[B] By small commercial airplanes, we mean those airplanes operating 
under part 135 of title 14 C.F.R. Among other things, part 135 covers 
commuter operations on airplanes, other than turbojet powered 
airplanes, with nine passenger seats or less, and a payload capacity 
of 7,500 pounds or less. Most commuter, air tour, and air taxi 
operators and medical services (when a patient is on board) fall under 
the purview of part 135. By noncommercial airplanes, we mean airplanes 
that are privately operated under 14 C.F.R. part 91. These types of 
operations are often referred to as "general aviation" and include 
flights for recreation and training. Although noncommercial flights 
usually involve small aircraft, the definition depends on the nature 
of the operation not the size of the aircraft. 

[C] By large commercial airplanes, we mean those airplanes operating 
under part 121 of title 14 C.F.R. part 121. Among other things, part 
121 applies to air carrier operations involving turbojet airplanes or 
any airplane with a seating capacity of more than nine passenger seats 
or a maximum payload capacity of more than 7,500 pounds, as defined 
under 14 C.F.R. § 119.3. See 14 C.F.R. section § 121.1. 

[End of table] 

Tower Air Inc. Flight #41: 

On December 20, 1995, Tower Air Flight #41, a Boeing B-747, veered off 
the side of the runway during an attempted takeoff at John F. Kennedy 
International Airport. Twenty-four of the 468 people on board 
sustained minor injuries, one person received serious injuries, and 
the airplane sustained substantial damage. NTSB found that the 
probable cause of the accident was the captain's failure to reject 
takeoff in a timely manner when the airplane lost control on a 
slippery runway. Inadequate operating procedures by Boeing and Tower 
Air also contributed to the accident. 

Table 3: Recommendations Resulting from the Accident Involving Tower 
Air Inc. Flight #41: 

Recommendation number, date issued, and date closed (where 
applicable): A-96-150; Issued 12/20/1996; Closed 5/13/1998; 
Recipient: FAA; 
Summary of recommendation: Require Boeing to revise its operating 
procedures to warn flight crews against using the tiller during 
slippery runway operations and to provide appropriate limitations on 
tiller use during these operations; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-96-151; Issued 12/20/1996; Closed 10/6/1998; 
Recipient: FAA; 
Summary of recommendation: Inform FAA inspectors of the circumstances 
of this accident. Require the review, and modification as required, of 
each air carrier's takeoff procedure regarding pilot hand position 
with respect to the tiller; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-96-152; Issued 12/20/1996; Closed 10/6/1998; 
Recipient: FAA; 
Summary of recommendation: Require Boeing to develop criteria for 
making a rapid and accurate decision to reject a takeoff under 
slippery runway conditions; 
then require that B-747 flight, operating, and training manuals be 
revised accordingly; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-96-153; Issued 12/20/1996; Closed 12/26/2001; 
Recipient: FAA; 
Summary of recommendation: Ensure that Boeing 747 air carrier flight 
crew training simulators accurately simulate the aircraft's slippery 
runway handling characteristics; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-96-154; Issued 12/20/1996; Closed 12/26/2001; 
Recipient: FAA; 
Summary of recommendation: Direct FAA inspectors assigned to Boeing 
747 operators to enhance simulator training for slippery runway 
operations; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-96-164; Issued 12/20/1996; Closed 6/14/2002; 
Recipient: FAA; 
Summary of recommendation: Require a rulemaking advisory group to 
establish runway friction measurements that are useful to pilots and 
air carriers during slippery runway operations; 
Status: Closed--reconsidered. 

Source: NTSB. 

[End of table] 

ValuJet Airlines Flight #558: 

On January 7, 1996, ValuJet Airlines Flight #558 touched down short of 
the runway at the Nashville International Airport. Of the 93 people on 
board, 5 received minor injuries. The airplane sustained substantial 
damage. NTSB found that this accident was caused by flight crew error 
and that ValuJet's incomplete manuals and guidance contributed to the 
accident. 

Table 4: Recommendations Resulting from the Accident Involving ValuJet 
Flight #558: 

Recommendation number, date issued, and date closed (where 
applicable): A-96-166; Issued 12/20/1996; Closed 12/19/1997; 
Recipient: FAA; 
Summary of recommendation: Require all airlines to review their 
operations and maintenance manuals and, if necessary, adjust or expand 
these manuals to reflect the manufacturer's recommended cold weather 
nosegear servicing procedures; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-96-172; Issued 12/20/1996; Closed 7/25/2001; 
Recipient: ValuJet; 
Summary of recommendation: Develop, immediately, a more extensive and 
accurate winter operations manual, with corresponding adjustments to 
maintenance procedures, to reflect the manufacturer's cold weather 
nosegear servicing procedures; 
Status: Closed--acceptable action. 

Source: NTSB. 

[End of table] 

Comair Airlines Flight #3272: 

On January 9, 1997, Comair Flight #3272 (an Embraer EMB-120 aircraft) 
crashed near Monroe, Michigan. All 29 people on board were killed. The 
airplane was destroyed by impact forces and postcrash fire. NTSB found 
that the airplane lost control when it accumulated a layer of ice on 
its lifting surfaces and failed to maintain sufficient airspeed. 

Table 5: Recommendations Resulting from the Crash of Comair Airlines 
Flight #3272: 

Recommendation number, date issued, and date closed (where 
applicable): A-97-31; Issued 5/21/1997; Closed 8/20/1999; 
Recipient: FAA; 
Summary of recommendation: Require air carriers to reflect FAA-
approved minimum airspeeds, including those for flight in icing 
conditions, in their EMB-120 operating manuals; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-97-32; Issued 5/21/1997; Closed 8/20/1999; 
Recipient: FAA; 
Summary of recommendation: Ensure that the deicing information and 
procedures in air carrier's EMB-120 operating manuals and training 
programs are consistent with the revised Embraer EMB-120 airplane 
flight manual; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-97-33; Issued 5/21/1997; Closed 8/20/1999; 
Recipient: FAA; 
Summary of recommendation: Direct FAA inspectors to ensure that EMB-
120 operators train flight crews to recognize icing conditions and 
emphasize the need to adhere to the flight manual's procedure for 
using deicing equipment; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-97-34; Issued 5/21/1997; Closed 7/8/1998; 
Recipient: FAA; 
Summary of recommendation: Require that all EMB-120 aircraft be 
equipped with automated ice detection and crew alerting systems for 
structural ice buildup; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-98-88; Issued 11/30/1998; Closed 3/9/2000; 
Recipient: FAA; 
Summary of recommendation: Amend the definition of trace ice in FAA 
documents so that they do not indicate that trace icing is not 
hazardous; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-98-89; Issued 11/30/1998; 
Recipient: FAA; 
Summary of recommendation: Require FAA inspectors to discuss airplane 
flight manual revisions or manufacturers' operational bulletins with 
affected air carrier operators. Encourage air carriers to share the 
information with pilots; 
Status: Open--acceptable response. 

Recommendation number, date issued, and date closed (where 
applicable): A-98-90; Issued 11/30/1998; Closed 1/3/2002; 
Recipient: FAA; 
Summary of recommendation: Educate manufacturers, operators, and 
pilots of turboprop airplanes in which ice bridging is not a concern 
on the dangers of accumulating thin, rough ice; the importance of 
activating deice boots as soon as the airplane enters icing conditions; 
and the importance of maintaining minimum airspeeds in icing 
conditions[A]; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-98-91; Issued 11/30/1998; Closed 2/27/2007; 
Recipient: FAA; 
Summary of recommendation: Require manufacturers and operators of 
turboprop airplanes in which ice bridging is not a concern to review 
and revise their manuals and training programs to emphasize that 
deicing equipment as soon as the airplane enters icing conditions; 
Status: Closed--unacceptable action/superseded; Superseded by A-07-14. 

Recommendation number, date issued, and date closed (where 
applicable): A-98-92; Issued 11/30/1998; Closed 10/16/2008; 
Recipient: FAA; 
Summary of recommendation: Conduct research to identify realistic ice 
accumulations and determine the effects and dangers of such ice 
accumulations. The information developed through such research should 
be incorporated into aircraft certification requirements and pilot 
training programs; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-98-93; Issued 11/30/1998; Closed 3/12/2001; 
Recipient: FAA; 
Summary of recommendation: Work with industry to develop effective ice 
detection and protection systems that will keep aircraft surfaces free 
of ice. Then, require installation of such systems on aircraft 
certified for flight in icing conditions; 
Status: Closed--unacceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-98-94; Issued 11/30/1998; Closed 1/19/2006; 
Recipient: FAA; 
Summary of recommendation: Require jet engine aircraft manufacturers 
to provide minimum airspeed information, with consideration of various 
types, amounts, and locations of ice accumulation; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-98-95; Issued 11/30/1998; Closed 9/15/2003; 
Recipient: FAA; 
Summary of recommendation: Require jet engine aircraft operators to 
incorporate the manufacturer's minimum airspeeds in their operating 
manuals and pilot training programs, with emphasis on maintaining 
minimum safe airspeeds while operating in icing conditions; 
Status: Closed--acceptable alternate action. 

Recommendation number, date issued, and date closed (where 
applicable): A-98-96; Issued 11/30/1998; 
Recipient: FAA; 
Summary of recommendation: Require the manufacturers and operators of 
aircraft certified to operate in icing conditions to install systems 
that provide a cockpit warning before the onset of a stall when the 
aircraft is operating in icing conditions; 
Status: Open--unacceptable response. 

Recommendation number, date issued, and date closed (where 
applicable): A-98-97; Issued 11/30/1998; Closed 1/12/2001; 
Recipient: FAA; 
Summary of recommendation: Require operators of turboprop aircraft to 
require pilots to disengage the autopilot and fly the aircraft 
manually when anti-ice systems are activated; 
Status: Closed--unacceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-98-98; Issued 11/30/1998; Closed 7/8/2009; 
Recipient: FAA; 
Summary of recommendation: Require all manufacturers of transport-
category airplanes with autopilot to provide a cockpit aural warning 
to alert pilots when the airplane's pitch or roll angle increases 
beyond the autopilot's maximum limits.[B]; 
Status: Closed--unacceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-98-99; Issued 11/30/1998; Closed 3/9/2000; 
Recipient: FAA; 
Summary of recommendation: Ensure that airplanes are adequately tested 
for the conditions in which they are certified to operate. This should 
include identifying ice shapes that form on aircraft surfaces, 
determining the effects of these ice shapes on flight performance, and 
incorporating this information into certification requirements; 
Status: Closed--unacceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-98-100; Issued 11/30/1998; Closed 2/27/2007; 
Recipient: FAA; 
Summary of recommendation: When the revised icing certification 
standards are complete, ensure that all turboprop airplanes that are 
currently certified to fly in icing conditions meet the requirements 
of the revised standards; 
Status: Closed--unacceptable action/superseded; Superseded by; A-07-16. 

Recommendation number, date issued, and date closed (where 
applicable): A-98-101; Issued 11/30/1998; Closed 5/10/2006; 
Recipient: FAA; 
Summary of recommendation: Review turboprop airplane manufacturers' 
flight manuals and air carrier operating manuals to ensure that they 
provide operational procedures for flight in icing conditions; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-98-102; Issued 11/30/1998; 
Recipient: FAA; 
Summary of recommendation: Require air carriers to adopt the operating 
procedures in the manufacturer's flight manual or provide written 
justification that an alternative procedure is equally safe; 
Status: Open--acceptable response. 

Recommendation number, date issued, and date closed (where 
applicable): A-98-105; Issued 11/30/1998; Closed 5/6/2003; 
Recipient: FAA; 
Summary of recommendation: Periodically remind pilots of their 
responsibility to report weather conditions that could affect the 
safety of other flights; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-98-106; Issued 11/30/1998; Closed 3/23/2000; 
Recipient: FAA; 
Summary of recommendation: Require that information provided to 
arriving and departing aircraft includes information on pilot reports 
of icing conditions; 
Status: Closed--reconsidered. 

Recommendation number, date issued, and date closed (where 
applicable): A-98-107; Issued 11/30/1998; Closed 8/19/2004; 
Recipient: NASA; 
Summary of recommendation: Educate manufacturers, operators, and 
pilots of turboprop airplanes on the hazards of thin, rough ice 
buildup; the importance of activating deicing boots as soon as the 
airplane enters icing conditions (for those airplanes in which ice 
bridging is not a concern); 
and the importance of maintaining minimum airspeeds in icing 
conditions; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-98-108; Issued 11/30/1998; 
Recipient: NASA; 
Summary of recommendation: Identify realistic ice accumulation 
configurations and determine their effect on aircraft performance. 
Incorporate this information into aircraft certification requirements 
and pilot training programs; 
Status: Open--acceptable response. 

Source: NTSB. 

[A] A turboprop airplane is an airplane with a turboprop engine, which 
is a hybrid engine that provides jet thrust and also drives a 
propeller. 

[B] In general, a transport category airplane is an airplane with 
maximum takeoff weight (MTOW) greater than 12,500 pounds or with 10 or 
more passenger seats, except for propeller-driven, multi-engine 
airplanes, in which case the transport category airplanes are those 
with MTOW greater than 19,000 pounds or with 20 or more passenger 
seats. FAA certifies the design of transport category airplanes under 
14 CFR part 25. 

[End of table] 

Reno Air Flight #153: 

On March 14, 1997, Reno Air Flight #153, a McDonnell Douglas MD-87 
airplane experienced a partial power loss in both engines during 
takeoff from Detroit, Michigan. The airplane returned to Detroit and 
landed without further incident. NTSB found that ice was present on 
the wings at takeoff, despite tactile wing inspections by the flight 
crew. The wing ice was ingested by the engines, blocking engine 
airflow. 

Table 6: Recommendations Resulting from the Incident Involving Reno 
Air Flight #153: 

Recommendation number, date issued, and date closed (where 
applicable): A-97-121; Issued: 12/22/1997; Closed: 7/20/1998; 
Recipient: FAA; 
Summary of recommendation: Alert FAA inspectors, and through them all 
affected air carrier flight crews, of the details of the Reno Air 
incident and the need to reduce power when engine airflow is blocked 
to minimize engine damage and ensure safe landing; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-97-122; Issued 12/22/1997; Closed 7/25/2001; 
Recipient: FAA; 
Summary of recommendation: Require MD-80 and MD-90 airplanes to have 
more reliable equipment for preventing or detecting wing ice before 
every flight in lieu of tactile inspection; 
Status: Closed--acceptable action. 

Source: NTSB. 

[End of table] 

Garuda Indonesia Airlines Flight #421: 

On January 16, 2002, Garuda Indonesia Airlines Flight #421 lost power 
in both engines when approaching the city of Yogyakrta on Java Island 
in Indonesia. After several unsuccessful attempts to restart the 
engines, the flight crew made an emergency water landing. Of the 60 
people on board, 1 was killed, 12 received serious injuries, and 10 
received minor injuries. The airplane was substantially damaged. Based 
on weather data and the cockpit recording, NTSB suspects that rain and 
hail ingestion may have caused the engine failure. 

Table 7: Recommendations Resulting from the Accident Involving Garuda 
Indonesia Airlines Flight #4184: 

Recommendation number, date issued, and date closed (where 
applicable): A-05-019; Issued 8/31/2005; 
Recipient: FAA; 
Summary of recommendation: Complete the review of the current turbofan 
engine certification standards for rain and hail intake and revise 
these standards if necessary[A]; 
Status: Open--acceptable response. 

[End of table] 

Source: NTSB. 

[A] A turbofan engine is a type of jet engine in which the core engine 
is surrounded by a fan in the front and an additional turbine in the 
rear. 

Spirit Airlines Flight #970: 

On June 4, 2002, Spirit Airlines Flight #970 experienced a gradual 
power loss in both engines and a stall warning while in flight near 
Wichita, Kansas. Pilots disengaged autopilot, turned on engine 
ignition, activated the engine anti-ice system, and initiated a 
descent. The flight landed safely and there were no injuries. 

Table 8: Recommendations Resulting from the Incident Involving Spirit 
Airlines Flight #970: 

Recommendation number, date issued, and date closed (where 
applicable): A-04-34; Issued 4/29/2004; Closed 10/21/2004; 
Recipient: FAA; 
Summary of recommendation: Have FAA inspectors alert affected air 
carrier flight crews about the Spirit Airlines Flight #970 encounter 
with icing conditions. Emphasize the need to be alert to the signs of 
high-altitude icing conditions, the effect of these conditions on 
airplane and engine performance, and the need for appropriate use of 
engine icing protection equipment; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-04-35; Issued 4/29/2004; 
Recipient: FAA; 
Summary of recommendation: Pursue research to develop an ice detector 
that would alert pilots to icing of certain aircraft equipment and 
require that the ice detector be installed on new production turbojet 
airplanes and retrofitted to existing turbojet airplanes; 
Status: Open--acceptable response. 

Source: NTSB. 

[End of table] 

Icing Accidents and Incidents Involving Cessna 208 Series Airplanes: 

From 1987 to 2003, there were 26 icing-related accidents and incidents 
involving Cessna 208 series airplanes, resulting in at least 36 
fatalities. NTSB's findings raised concerns about possible 
deficiencies the certification standards applicable to Cessna 208 
series airplanes, the cold weather operational procedures used by 
Cessna 208 pilots, or the design of the airplane and its deicing and 
anti-icing systems. 

Table 9: Recommendations Made to Address Accidents and Incidents 
Involving Cessna 208 Series Airplanes: 

Recommendation number, date issued, and date closed (where 
applicable): A-04-64; Issued 12/15/2004; Closed 1/29/2009; 
Recipient: FAA; 
Summary of recommendation: Require all pilots and operators of those 
Cessna 208 series airplanes equipped for flight in icing conditions to 
undergo annual training for ground deicing and flight into icing 
conditions; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-04-65; Issued 12/15/2004; Closed 1/7/2009; 
Recipient: FAA; 
Summary of recommendation: Require the Cessna Aircraft Company to 
develop effective procedures and guidance to minimize the chance of 
ground and in-flight icing accidents and incidents for Cessna 208 
series aircraft. FAA should then verify that these procedures and 
guidance materials are incorporated into Cessna 208 operator manuals 
and training programs; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-04-66; Issued 12/15/2004; Closed 1/7/2009; 
Recipient: FAA; 
Summary of recommendation: Require pilots and operators of Cessna 208 
series airplanes to examine the wing and other surfaces to ensure that 
they are free of ice, snow, or both before any flight from a location 
where temperatures are conducive to frost and ground icing; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-04-67; Issued 12/15/2004; 
Recipient: FAA; 
Summary of recommendation: Evaluate FAA's current surveillance 
procedures for operators of Cessna 208 series airplanes equipped for 
flight into icing conditions to determine whether the surveillance 
effectively ensures that these operators are in compliance with 
federal deicing requirements. If necessary, modify the surveillance 
procedures to ensure such compliance; 
Status: Open--acceptable response. 

Source: NTSB. 

[End of table] 

Engine Power Loss in Raytheon Beechjet 400 Series Airplanes: 

From 2004 to 2006, three incidents occurred in the United States in 
which Raytheon Beechjet airplanes lost power in both Pratt & Whitney 
JT15D engines. A similar incident occurred in Brazil in 2000. NTSB is 
concerned about this recent onset of dual-engine failures and the 
sustained loss of power that occurred in each event after several 
attempts to restart the engine. A study by Pratt & Whitey Canada (the 
engine manufacturer) found that with the engine anti-ice turned off, 
it was possible for ice crystals to build up in the engines and that 
the buildup could lead to airflow disruption, engine failure, or both. 

Table 10: Recommendations Resulting from Power Loss in Raytheon 
Beechjet 400 Series Airplanes: 

Recommendation number, date issued, and date closed (where 
applicable): A-06-56; Issued 8/25/2006; Closed 5/18/2007; 
Recipient: FAA; 
Summary of recommendation: Immediately require Beechjet 400 pilots to 
activate engine ice protection systems in weather conditions conducive 
to engine icing or before a power reduction in certain weather 
conditions; 
Status: Closed--exceeds recommended action. 

Recommendation number, date issued, and date closed (where 
applicable): A-06-57; Issued 8/25/2006; Closed 5/18/2007; 
Recipient: FAA; 
Summary of recommendation: Require Raytheon to incorporate information 
on ice protection system operation and ice formation into the Beechjet 
400 airplane flight manual; 
Status: Closed--exceeds recommended action. 

Recommendation number, date issued, and date closed (where 
applicable): A-06-58; Issued 8/25/2006; Closed 2/29/2008; 
Recipient: FAA; 
Summary of recommendation: Incorporate information on ice protection 
system operation and ice formation into the flight manuals of aircraft 
with JT15D engines; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-06-59; Issued 8/25/2006; 
Recipient: FAA; 
Summary of recommendation: Pursue research to develop an ice detector 
that would alert pilots of engine icing. Require that such an ice 
detector be installed on new turbojet engines and retrofitted to 
existing turbojet engines; 
Status: Open--acceptable alternate response. 

Source: NTSB. 

[End of table] 

Glo-Air Flight #73: 

On November 28, 2004, Glo-Air Flight #73 crashed during an attempted 
takeoff in snowing conditions. Before the accident flight, the 
airplane was parked for 45 minutes while wet snow fell, and the 
airplane was not deiced before takeoff. Three people on board were 
killed, and three received serious injuries. The airplane was 
destroyed by impact forces and postcrash fire. NTSB found that the 
accident was caused by the flight crew's failure to ensure that the 
airplane's wings were free of ice and snow prior to takeoff. 

Table 11: Recommendations Resulting from the Crash of Glo-Air Flight 
#73: 

Recommendation number, date issued, and date closed (where 
applicable): A-06-042; Issued 8/4/2006; 
Recipient: FAA; 
Summary of recommendation: Develop training aids to accurately depict 
small amounts of wing ice buildup and require all commercial airplane 
operators to use them in their initial and recurrent training; 
Status: Open--unacceptable response. 

Source: NTSB. 

[End of table] 

Martinair Circuit City Accident in Pueblo, Colorado: 

On February 16, 2005, a Cessna Citation 560, operated by Martinair for 
Circuit City Stores, crashed near Pueblo, Colorado. Eight people were 
killed, and the airplane was destroyed by impact forces and postcrash 
fire. NTSB found that this accident was caused by the flight crew's 
failure to monitor and maintain airspeed and comply with deicing 
system activation procedures. NTSB also found that FAA's failure to 
establish adequate icing certification requirements contributed to the 
accident. 

Table 12: Recommendations Resulting from the Martinair Circuit City 
Crash: 

Recommendation number, date issued, and date closed (where 
applicable): A-07-12; Issued 2/27/2007; 
Recipient: FAA; 
Summary of recommendation: Require that operational training in the 
Cessna 560 airplane emphasize that the airplane flight manual requires 
pilots to increase the airspeed and operate the deice boots in certain 
phases of flight when ice is present on the wings; 
Status: Open--acceptable response. 

Recommendation number, date issued, and date closed (where 
applicable): A-07-13; Issued 2/27/2007; 
Recipient: FAA; 
Summary of recommendation: Require that all pilot training programs 
teach and emphasize monitoring skills and workload management and 
include opportunities to practice and demonstrate proficiencies in 
these areas; 
Status: Open--unacceptable response. 

Recommendation number, date issued, and date closed (where 
applicable): A-07-14; Most Wanted; Issued 2/27/2007; 
Recipient: FAA; 
Summary of recommendation: Require manufacturers and operators of 
airplanes with deice boots to revise their manuals and training 
programs to emphasize that deice boots should be activated as soon as 
the airplane enters icing conditions; 
Status: Open--acceptable response; Supersedes A-98-91. 

Recommendation number, date issued, and date closed (where 
applicable): A-07-15; Issued 2/27/2007; 
Recipient: FAA; 
Summary of recommendation: Require all airplanes with deice boots that 
are certified to fly in icing conditions to have a mode that would 
automatically continue to cycle the deice boots once the system has 
been activated; 
Status: Open--acceptable response. 

Recommendation number, date issued, and date closed (where 
applicable): A-07-16; Most Wanted; Issued 2/27/2007; 
Recipient: FAA; 
Summary of recommendation: When the revised icing certification 
standards (recommended in Safety Recommendations A-96-54 and A-98-92) 
are complete, ensure that airplanes with deice boots fulfill the 
requirements of the revised icing certification standards; 
Status: Open--unacceptable response; Supersedes A-98-100. 

Recommendation number, date issued, and date closed (where 
applicable): A-07-17; Issued 2/27/2007; 
Recipient: FAA; 
Summary of recommendation: Require modification of the Cessna 506 
airplane's stall warning system so that it accounts for the size, 
type, and distribution of ice buildup; 
Status: Open--acceptable response. 

Source: NTSB. 

[End of table] 

Midwest Airlines Flight #490: 

On May 12, 2005, Midwest Airlines Flight #490 experienced unreliable 
airspeed indications during flight in heavy rain and icing conditions. 
The airplane experienced significant gains and losses in altitude 
before the crew was able to regain control and divert to Kirksville, 
Missouri. Results of NTSB's investigation indicate that this incident 
was caused by the flight crew's failure to activate the air data 
sensor heating system and that cockpit warnings were ineffective at 
alerting the crew to the air data sensor problem. 

Table 13: Recommendations Resulting from the Crash of Midwest Airlines 
Flight #490: 

Recommendation number, date issued, and date closed (where 
applicable): A-07-55; Issued 9/13/2007; 
Recipient: FAA; 
Summary of recommendation: Require the air data sensor heating systems 
on new transport category aircraft to automatically activate after 
engine start; 
Status: Open--acceptable response. 

Recommendation number, date issued, and date closed (where 
applicable): A-07-56; Issued 9/13/2007; 
Recipient: FAA; 
Summary of recommendation: Require modification of existing transport 
category aircraft that currently require manual activation of the air 
data sensor heating system so that this system is activated 
automatically. For airplanes that cannot be modified, require an 
upgraded cockpit warning when the heating system fails to activate; 
Status: Open--acceptable response. 

Source: NTSB. 

[End of table] 

Southwest Airlines Flight #1248: 

On December 8, 2005, Southwest Airlines Flight #1248 landed on a snow- 
covered runway in Chicago, Illinois. The airplane departed the end of 
the runway and rolled through airport fences and then into traffic on 
an off-airport street. The airplane came to a stop after impacting two 
cars, which resulted in the death of a child passenger in one of the 
vehicles. NTSB found that this accident was caused by the pilots' 
failure to use reverse thrust in a timely manner to safely slow or 
stop the airplane after landing. 

Table 14: Recommendations Resulting from the Accident Involving 
Southwest Airlines Flight #1248: 

Recommendation number, date issued, and date closed (where 
applicable): A-06-16; Issued 1/27/2006; Closed 10/4/2007; 
Recipient: FAA; 
Summary of recommendation: Immediately prohibit large commercial 
operators from factoring use of the reverse thrust deceleration system 
into landing performance calculations; 
Status: Closed--unacceptable action; superseded; Superseded by A-07-57. 

Recommendation number, date issued, and date closed (where 
applicable): A-07-57; Issued 10/4/2007; 
Recipient: FAA; 
Summary of recommendation: Immediately require large commercial, small 
commercial, and some noncommercial operators to assess the distance 
needed to land before every landing, incorporating a 15 percent safety 
margin; 
Status: Open--unacceptable response; Supersedes A-06-16. 

Recommendation number, date issued, and date closed (where 
applicable): A-07-59; Issued 10/16/2007; 
Recipient: FAA; 
Summary of recommendation: Require large commercial and small 
commercial operators to provide clear guidance and training to pilots 
and dispatchers on company policy regarding surface condition and 
braking performance reporting, as well as landing distance 
calculations; 
Status: Open--acceptable response. 

Recommendation number, date issued, and date closed (where 
applicable): A-07-61; Issued 10/16/2007; 
Recipient: FAA; 
Summary of recommendation: Require large commercial, small commercial, 
and some noncommercial operators to make landing distance assessments 
before every landing based on standardized methodology, using the most 
conservative interpretation available, and including a 15 percent 
safety margin; 
Status: Open--acceptable response. 

Recommendation number, date issued, and date closed (where 
applicable): A-07-62; Issued 10/16/2007; 
Recipient: FAA; 
Summary of recommendation: Develop and issue formal guidance regarding 
runway surface condition reports; 
Status: Open--acceptable response. 

Recommendation number, date issued, and date closed (where 
applicable): A-07-63; Issued 10/16/2007; 
Recipient: FAA; 
Summary of recommendation: Establish a minimum standard for large 
commercial and small commercial operators to use in comparing an 
airplane's braking ability to runway condition reports; 
Status: Open--acceptable response. 

Recommendation number, date issued, and date closed (where 
applicable): A-07-64; Issued 10/16/2007; 
Recipient: FAA; 
Summary of recommendation: Show whether it is feasible to outfit 
transport-category airplanes with the means to track and communicate 
airplane braking ability needed to stop the airplane during landing. 
If feasible, require transport category airplane operators to use such 
equipment and procedures; 
Status: Open--acceptable response. 

Source: NTSB. 

[End of table] 

International Cessna 208 Series Aircraft Accidents: 

NTSB participated in two foreign investigations of fatal accidents 
involving Cessna 208 series airplanes in icing conditions. These 
accidents occurred in Winnipeg, Manitoba, Canada and Moscow, Russia in 
2005. NTSB found the following problems with Cessna 208 series 
airplanes: in both accidents, the minimum operating airspeed in icing 
conditions did not provide an adequate safety margin. Specifically, in 
the Winnipeg accident, the pilot had very little time to escape icing 
conditions; and in the Moscow accident, the pilots did not have 
adequate cues of airplane performance degradation. 

Table 15: Recommendations Resulting from Two International General 
Aviation Accidents: 

Recommendation number, date issued, and date closed (where 
applicable): A-06-1; Issued 1/17/2006; Closed 11/15/2006; 
Recipient: FAA; 
Summary of recommendation: Require all operators of Cessna 208 series 
airplanes to maintain sufficient airspeed during flight in icing 
conditions; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-06-2; Issued 1/17/2006; Closed 11/15/2006; 
Recipient: FAA; 
Summary of recommendation: Prohibit operators of Cessna 208 series 
airplanes from flying into icing conditions more severe than light 
icing; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-06-3; Issued 1/17/2006; Closed 11/15/2006; 
Recipient: FAA; 
Summary of recommendation: Require all operators of Cessna 208 series 
airplanes to disengage the autopilot and fly the airplane manually 
when operating in icing conditions; 
Status: Closed--acceptable action. 

Source: NTSB. 

[End of table] 

American Eagle Flight #3008: 

On January 2, 2006, American Eagle Flight #3008, a Saab-Scania AB 
SF340B+, encountered icing conditions in-flight and lost control. 
After losing altitude, pilots regained control and continued without 
further incident. NTSB found that the aircraft's performance 
degradation occurred at airspeeds above the current minimum safe 
speeds. NTSB also found that the aircraft's stall warning would have 
activated if the "ice speed" modification to the stall warning system 
had been used. Furthermore, the airplane did not have an ice detection 
system, which would have alerted crew to ice buildup, and use of 
autopilot likely reduced the crew's perception of aircraft performance. 

Table 16: Recommendations Resulting from the Incident Involving 
American Eagle Flight #3008: 

Recommendation number, date issued, and date closed (where 
applicable): A-06-48; Issued 7/10/2006; Closed 2/4/2009; 
Recipient: FAA; 
Summary of recommendation: Require operators of Saab SF340 airplanes 
to instruct pilots to maintain sufficient airspeed in icing conditions 
and to exit icing conditions as soon as degraded performance prevents 
the airplane from maintaining sufficient airspeed; 
Status: Closed--acceptable action. 

Recommendation number, date issued, and date closed (where 
applicable): A-06-49; Issued 7/10/2006; 
Recipient: FAA; 
Summary of recommendation: Require modified stall protection systems 
in Saab SF340 series airplanes certified to fly in known icing 
conditions; 
Status: Open--acceptable response. 

Recommendation number, date issued, and date closed (where 
applicable): A-06-50; Issued 7/10/2006; Closed 2/4/2009; 
Recipient: FAA; 
Summary of recommendation: Require the installation of an icing 
detection system on Saab SF340 series airplanes; 
Status: Closed--acceptable alternate action. 

Recommendation number, date issued, and date closed (where 
applicable): A-06-51; Issued 7/10/2006; 
Recipient: FAA; 
Summary of recommendation: Require operators of turboprop airplanes to 
instruct pilots to disengage the autopilot and fly manually in icing 
conditions, except during periods of high workload; 
Status: Open--await response. 

Source: NTSB. 

[End of table] 

Delta Connection Flight #6448: 

On February 18, 2007, Delta Connection Flight #6448 overran the end of 
the runway while landing in snowy conditions. The aircraft struck an 
airport perimeter fence and its nose gear collapsed. Three passengers 
received minor injuries. NTSB determined that the accident was caused 
by flight crew errors, including failure to recognize that a safe 
landing could not be accomplished. 

Table 17: Recommendations Resulting from the Crash of Delta Connection 
Flight #6448: 

Recommendation number, date issued, and date closed (where 
applicable): A-08-17; Issued 4/15/2008; 
Recipient: FAA; 
Summary of recommendation: Require large commercial, small commercial, 
and certain noncommercial operators to include practice for landing on 
contaminated runways into simulator training for turbojet airplanes; 
Status: Open--acceptable alternate response. 

Source: NTSB. 

[End of table] 

Pinnacle Airlines Flight #4712: 

On April 12, 2007, Pinnacle Airlines Flight #4712 ran off the runway 
after landing in snowy conditions at Traverse City, Michigan. There 
were no injuries, but the aircraft was substantially damaged. NTSB 
found that this accident was caused by the pilots' decision to land 
without performing a landing distance assessment. Airport personnel's 
use of ambiguous language in providing runway braking information also 
contributed to the accident. 

Table 18: Recommendations Resulting from the Accident Involving 
Pinnacle Airlines Flight #4712: 

Recommendation number, date issued, and date closed (where 
applicable): A-08-41; Issued 6/17/2008; 
Recipient: FAA; 
Summary of recommendation: Address the need for initial training on 
conducting landing distance assessments before landing on contaminated 
runways; 
Status: Open--acceptable response. 

Recommendation number, date issued, and date closed (where 
applicable): A-08-42; Issued 6/17/2008; Closed 6/22/2009; 
Recipient: FAA; 
Summary of recommendation: Alert airports of the circumstances of this 
accident, urging all airports to ensure that radio communications 
criteria are met; 
Status: Open--acceptable response. 

Recommendation number, date issued, and date closed (where 
applicable): A-08-43; Issued 6/17/2008; 
Recipient: FAA; 
Summary of recommendation: Require airport operators to include 
criteria for runway contamination and runway friction assessments in 
their airport's snow and ice control plan. Fulfillment of these 
criteria should trigger closure of the affected runway; 
Status: Open--acceptable response. 

Source: NTSB. 

[End of table] 

[End of section] 

Footnote: 

[1] NTSB has closed 8 of these recommendations as "unacceptable 
response" by FAA; has classified 7 of the open recommendations as 
"unacceptable response" by FAA; has closed 3 of these recommendations 
after concurring with FAA's rationales for disagreeing with the 
recommendations; and is awaiting FAA's response on 1 of these 
recommendations. 

[End of section] 

Contact Information: 

If you have questions concerning these data, please contact Gerald L. 
Dillingham at (202) 512-2834 or dillinghamg@gao.gov. 

Copyright: 

This is a work of the U.S. government and is not subject to copyright 
protection in the United States. The published product may be 
reproduced and distributed in its entirety without further permission 
from GAO. However, because this work may contain copyrighted images or 
other material, permission from the copyright holder may be necessary 
if you wish to reproduce this material separately.