![](media/image1.wmf){width="0.5305555555555556in"
height="0.5361111111111111in"}

U.S. Department of

Transportation

**FEDERAL AVIATION**

**ADMINISTRATION**

> **DRAFT REGULATORY EVALUATION**

**Removal of Regulations Allowing for Polished Frost on Wings of
Airplanes**

Notice of Proposed Rulemaking

(14 CFR Parts 91, 125, and 135)

Office of Aviation Policy and Plans

Operations Regulatory Analysis Branch, APO-310

Marquise J. McGraw

March 21, 2008

**TABLE OF CONTENTS**

[EXECUTIVE SUMMARY i](#executive-summary)

[I. INTRODUCTION 1](#i.-introduction)

[II. BACKGROUND 1](#ii.-background)

[III. ACCIDENT HISTORY AND BENEFITS SIMULATION
3](#iii.-accident-history-and-benefits-simulation)

[IV. BENEFITS OF THE PROPOSED RULE 6](#__RefHeading___Toc193788650)

[V. COST OF THE PROPOSED RULE 8](#__RefHeading___Toc193788651)

[VI. CONCLUSION 15](#vi.-conclusion)

[VII. APPENDIX: LIST OF POLISHED FROST ACCIDENTS, 1982-2007
16](#vii.-appendix-list-of-polished-frost-accidents-1982-2007)

## EXECUTIVE SUMMARY

This Notice of Proposed Rulemaking proposes to remove references in the
Federal aviation regulations that allow takeoffs in situations where
frost is present on wings, stabilizing surfaces, or control surfaces,
when such frost has been "polished" to make it smooth. The FAA believes
these changes are necessary to improve aviation safety.

For the ten-year period from 2009 to 2018, total benefits are expected
to be about \$460,000 (\$320,000 discounted). Of these, \$433,000
(\$301,000 discounted) of the benefits would be realized in Alaska,
while the remaining \$27,000 (\$19,000 discounted) would be realized in
the mainland U.S.

Costs would depend on which of four alternatives (wing covers, storing
the aircraft in a hangar, deicing the surface areas, or waiting for the
frost to melt) are selected by operators. The FAA believes that using
wing covers is the least costly alternative. Assuming operators choose
to use wing covers, over the ten year period from 2009 to 2018, costs
would total roughly \$164,000 (\$130,000 discounted). Of these,
\$155,000 (\$123,000 discounted) would accrue to Alaska, and \$9,500
(\$7,500 discounted) would accrue to the mainland U.S. Since benefits
exceed costs for both Alaska and the mainland U.S., the FAA concludes
the proposed rule is cost-beneficial.

[]{.mark}

## []{.mark} {#section .unnumbered}

## I. INTRODUCTION

The FAA proposes to modify §§91.527 (a), 125.221 (a), and 135.227 (a) of
Chapter 14 of the CFR to remove any references that allow takeoffs in
situations where frost is present on wings, stabilizing surfaces, or
control surfaces, when such frost has been "polished" to make it smooth.
In addition, the FAA is taking the opportunity to correct the structure
of §135.227 (c). Currently, it appears the phrase beginning with "unless
the aircraft has..." applies only to paragraph (c)(2). However, that
clause applies to all the provisions of (c). The FAA is therefore
proposing to restructure paragraph (c).

## 

## II. BACKGROUND

Currently, §§91.527 (a), 125.221 (a), and 135.227 (a) allow pilots to
take off with frost adhering to wings or stabilizing or control surfaces
if that frost has been polished to make it smooth. This frost is
referred to as "polished frost." This procedure first appeared in the
[Federal Register]{.underline} as Civil Air Regulation Draft Release No.
60-13, a proposed revision of part 47 of the Civil Air Regulations, on
August 6, 1960. There was no preamble information or data to support or
justify the procedure.

Since 1960, the FAA and others have gathered an extensive amount of data
which suggests that any amount of contaminants on wings or critical
surfaces could be detrimental to the flight characteristics of an
aircraft. In fact, it is even more critical today than in the past that
wings are clear of any contaminants upon takeoff. As a result of the
design of the wings on today's aircraft, such surfaces are much more
sensitive to contaminants than those in the past. In Advisory Circular
(AC) 135-17, issued on December 14, 1994, the FAA recommends that all
wing frost be removed prior to takeoff, and states that if an operator
desires to polish the frost, the aircraft manufacturer's recommended
procedures should be followed. No current aircraft manufacturer,
however, has issued any recommended procedures for (1) polishing frost;
or (2) conducting operations with polished frost. In addition, the FAA
has no data to support practical guidance on determining how to polish
frost on a surface to make it acceptably smooth, other than completely
removing the frost and returning the airplane's surfaces to
uncontaminated smoothness. Moreover, the term "polished frost" is
ambiguous since no standard of acceptable smoothness is provided. Also,
means to ensure that the "polished frost" surface smoothness is
equivalent to that of the uncontaminated airplane surface is
operationally impractical. Subsequently, the FAA issued two Safety
Alerts for Operators (SAFOs)---06002, dated March 29, 2006 and 06014,
dated October 6, 2006 \-- advising against the practice of polishing
frost.

There have been a number of takeoff accidents that have occurred when
flight crews have consciously decided to take off without removing frost
from the wings of their aircraft. Following the January 4, 2002 accident
at Birmingham, England, the United Kingdom Aircraft Accident
Investigation Board issued Safety Recommendation 2003-54, recommended in
its Safety Recommendation 2003-54 that the FAA, and all Authorities who
follow FAA practice, delete all reference to 'Polished Frost' within
their regulations and ensure that the term is expunged from Operations
Manuals. In addition, the U.S. National Transportation Safety Board
(NTSB) has issued numerous safety alerts urging operators to ensure that
critical surfaces are free of all contamination prior to takeoff.
Accordingly, the FAA has determined that any attempt at polishing frost
increases the risk of unsafe flight.

## III. ACCIDENT HISTORY AND BENEFITS SIMULATION

The FAA has identified eleven accidents between 1982 and 2006 in which
individuals tried to "smooth" or "polish" frost on an aircraft's wing
before takeoff. Various techniques were used to do so. These included
running a rope against the wing surface, brushing the frost off by hand,
brushing the frost off using a broom, running a scraper across the wing
surface, or, in one case, using paper towels and credit cards to remove
the frost. In all eleven accidents the aircraft failed to lift off the
runway during takeoff or stalled shortly after becoming airborne. A list
of these eleven accidents, and the NTSB final report for each, is
included in the Appendix.

Nine of these accidents involved single-engine general aviation (GA)
aircraft operated under Part 91; the other two involved air taxi
aircraft operating under Part 135. Of these, there were two fatal
accidents, one accident involving minor injuries, and eight involving no
reported injuries. One plane was destroyed, while the other 10 were
substantially damaged. Six out of the 11 accidents occurred in Alaska.

The FAA used the last 20 years of available NTSB accident data
(1987-2006) for the analysis. That data was subdivided into eleven
ten-year periods, as shown in the table below. For each ten-year period
the FAA determined how many accidents occurred within that time. As
shown below in Table 1, the number of accidents occurring within each
10- year period ranged from 1 to 4.

+----------------------+-----------------------------------------------+
| **Table 1: Polished  |                                               |
| Frost Accidents by** |                                               |
|                      |                                               |
| **10-Year Period**   |                                               |
+----------------------+-----------------------------------------------+
| **Period**           | **Number of Accidents**                       |
+----------------------+-----------------------------------------------+
| 1987-1996            | 4                                             |
+----------------------+-----------------------------------------------+
| 1988-1997            | 2                                             |
+----------------------+-----------------------------------------------+
| 1989-1998            | 2                                             |
+----------------------+-----------------------------------------------+
| 1990-1999            | 1                                             |
+----------------------+-----------------------------------------------+
| 1991-2000            | 2                                             |
+----------------------+-----------------------------------------------+
| 1992-2001            | 2                                             |
+----------------------+-----------------------------------------------+
| 1993-2002            | 2                                             |
+----------------------+-----------------------------------------------+
| 1994-2003            | 3                                             |
+----------------------+-----------------------------------------------+
| 1995-2004            | 3                                             |
+----------------------+-----------------------------------------------+
| 1996-2006            | 4                                             |
+----------------------+-----------------------------------------------+
| 1997-2006            | 4                                             |
+----------------------+-----------------------------------------------+

The FAA used this information as the basis for a simulation. The
simulation was set up to provide total benefits for a given 10-year
period in the future. To do so, it was assumed the distribution of
accidents would roughly approximate a uniform distribution. This
distribution assumes that for a given ten-year period in the future,
there is an equal likelihood there would be one, two, three, or four
accidents attributable to polished frost within that period. Five
thousand trials were conducted, where each trial represented a future
ten-year period. The expected benefits were determined by averaging the
results of each of these 5,000 trials. Table 2 below lists the
simulation inputs, all of which were obtained from the accident data.

+-------------------------------------+--------------------------------+
| **Table 2: Probability Inputs Drawn |                                |
| From**                              |                                |
|                                     |                                |
| **Accident Data**                   |                                |
+-------------------------------------+--------------------------------+
| **Event**                           | **Probability**                |
+-------------------------------------+--------------------------------+
| Probability of Fatal Accident       | 0.18                           |
+-------------------------------------+--------------------------------+
|                                     |                                |
+-------------------------------------+--------------------------------+
| Injury - Fatal Accidents:           |                                |
+-------------------------------------+--------------------------------+
| Death                               | 0.62                           |
+-------------------------------------+--------------------------------+
| Significant Injury                  | 0.38                           |
+-------------------------------------+--------------------------------+
|                                     |                                |
+-------------------------------------+--------------------------------+
| Injury - Non-Fatal Accidents:       |                                |
+-------------------------------------+--------------------------------+
| Significant Injury                  | N/A                            |
+-------------------------------------+--------------------------------+
| Minor Injury                        | 0.05                           |
+-------------------------------------+--------------------------------+
| No Injury                           | 0.95                           |
+-------------------------------------+--------------------------------+
|                                     |                                |
+-------------------------------------+--------------------------------+
| Damage -- Fatal Accidents           |                                |
+-------------------------------------+--------------------------------+
| Destroyed                           | 0.5                            |
+-------------------------------------+--------------------------------+
| Substantial Damage                  | 0.5                            |
+-------------------------------------+--------------------------------+
|                                     |                                |
+-------------------------------------+--------------------------------+
| Damage -- Non-Fatal Accidents       |                                |
+-------------------------------------+--------------------------------+
| Destroyed                           | N/A                            |
+-------------------------------------+--------------------------------+
| Substantial Damage                  | 1.0                            |
+-------------------------------------+--------------------------------+
|                                     |                                |
+-------------------------------------+--------------------------------+
| Proportion of Part 125/135          | 0.18                           |
| Accidents in Sample                 |                                |
+-------------------------------------+--------------------------------+
|                                     |                                |
+-------------------------------------+--------------------------------+
| Proportion of Accidents In Alaska   | 0.55                           |
+-------------------------------------+--------------------------------+

Other assumptions incorporated into the model include:

-   The discount rate is 7 percent. Discounting takes place at the end
    of the year.

-   Benefits are assumed to be equal for each year within the simulated
    ten-year period which runs from 2009 -- 2018.

-   Each airplane flown subject to this rule has, on average, four
    seats. It is assumed that each seat on the plane is filled.

-   Value of a fatality: \$3,000,000

-   Value of a serious injury: \$580,700

-   Value of a minor injury: \$42,900

-   Value of a destroyed aircraft: \$629,869

-   Value of a substantially damaged aircraft: \$103,510

    []{#__RefHeading___Toc193788650 .anchor}**IV. BENEFITS OF THE
    PROPOSED RULE**

The simulation estimated total benefits for both the mainland U.S. and
Alaska based on all eleven accidents in the sample. Figure 3 below shows
the probability distribution of total benefits associated with the
entire sample of polished frost accidents. The mean was \$2.5 million,
the median was \$311,000, and the mode was \$104,000. The minimum
expected benefit was \$104,000 and the maximum expected benefit was
\$22.9 million. For the purposes of this analysis, the mean will be used
to represent the expected benefit so that the effects of fatal accidents
and accidents with many injuries or substantial aircraft damage are
fully accounted for.

Since this rulemaking would affect only operators under Parts 125, 135,
and those covered by subpart F of Part 91 (which includes all Part 91
subpart K operations, regardless of category, class, weight, powerplant
or number of engines), it was necessary to adjust the total benefits
from the entire sample of polished frost accidents to account for
that.[^1] There are two Part 135 accidents in our sample that fall
within the scope of the proposed rule. The other nine accidents in our
sample involve non-commercial general aviation, which are not subject to
this rulemaking. Therefore, the total benefits were reduced by a factor
of 9/11, or 81.8 percent, which is the proportion of general aviation
accidents in the sample. Final benefits were calculated by taking the
total simulated benefits (from all eleven accidents) and multiplying by
2/11, the proportion of Part 135 accidents in the sample.

![](media/image2.wmf){width="5.428472222222222in"
height="3.727777777777778in"}

Part 125/135 benefits were allocated to Alaska and the mainland U.S.
based on the number of aircraft affected by this rule in each location.
Data from the FAA Flight Standards Service, AFS-

200, On-Demand and Commuter Branch, indicate that there would be a total
of 188 aircraft affected by the proposed rule. Of these, 177 are in
Alaska. Therefore, 177/188, or 94.1 percent of the Part 125/135 benefits
were allocated to Alaska, while the remaining 5.9 percent were allocated
to the mainland U.S.

Over the ten year period from 2009 to 2018, the total benefits from this
proposed rule (the Part 125/135 benefits) are projected to be about
\$460,000 (\$320,000 discounted). Of those, \$433,000 (\$301,000
discounted) would accrue to Alaska, while the remaining \$27,000
(\$19,000 discounted) would accrue to the mainland U.S.

These benefits were attributed to averted accidents, injuries, and
aircraft damage. The FAA expects that under the proposed rule, pilots
and operators would protect their aircraft from frost formation using
wing covers. However, pilots and operators could use an approved
alternative such as waiting for the frost to completely melt, storing
the aircraft in a heated hangar, or deicing to remove all frost prior to
takeoff. Using any of these procedures would result in wings upon
takeoff that are free of frost, thereby preventing the accidents
described earlier in this analysis from occurring.

[]{#__RefHeading___Toc193788651 .anchor}**V. COST OF THE PROPOSED RULE**

Although the proposed rule would modify §§91.527 (a)(3), 125.221 (a),
and 135.227 (a), the proposed rule would only affect a subset of those
who operate under Parts 91, 125 or 135, as explained below.

[Cost to Part 91 operators]{.underline}

This proposed rule would modify §§91.527 (a)(3), which falls within Part
91, Subpart F. This subpart provides for the operation of large and
turbine-powered multiengine airplanes and all fractional ownership
program aircraft (regardless of category, class, weight, powerplant or
number of engines). Therefore, the revised provisions in subpart F in
this proposed rule would affect the operation of all fractional
ownership program aircraft under subpart K. The FAA requires that all
operators file Operations Specifications documents (OpSpecs) with the
FAA, providing the specifics of each operator's deicing plans and
procedures. If an operator wishes to use the polished frost technique,
he must state that in his OpSpec. The FAA must then approve the OpSpec
and, by extension, authorize an operator's use of the polished frost
technique.

Data provided by the FAA Flight Standards Service, AFS-200, On-Demand
and Commuter Branch, shows that out of 12 Part 91, Subpart K certificate
holders, none of these operators are authorized by the FAA, in their
OpSpecs, to use the polished frost technique in their ground deicing
programs. Since no Part 91K operators are authorized to use this
technique, this proposed rule would have no effect on their current
operations. Others operating under Part 91, such as recreational pilots,
are not covered under §91.527. Therefore, this rulemaking would not
affect other general aviation operators. As a result, the FAA concludes
that this rulemaking would impose no cost on Part 91 operators.

[Cost to Part 125 and 135 operators]{.underline}

Subparts 125.221 (a), and 135.227 (a) do apply to all Part 125 and 135
operators. However, not all Part 125 and 135 operators have the
authority to polish frost. Data from the FAA's Flight Standards Service,
On-Demand and Commuter Branch (AFS-200) show the FAA has granted this
authority, through their OpSpecs, to 57 operators operating 188
aircraft. Of these, 51 operators operating 177 aircraft are located in
Alaska. The FAA has determined there are at least four ways affected
operators can comply with the rule. These include: using wing covers,
delaying takeoff until the frost melts, storing the aircraft in a heated
hangar, or using deicing procedures to clear the wings of any
accumulated frost. The FAA believes that using wing covers is the least
costly of the four alternatives. A detailed discussion of each of these
alternatives follows below.

[Alternative 1: Wing Covers]{.underline}

Wing covers are light, durable covers made of special breathable fabrics
that can be placed over an aircraft's wing while it is not being flown.
These covers protect the aircraft from precipitation and prevent frost
build-up. Each set of wing covers weighs about 10 pounds. They are
designed to be folded and transported with the aircraft.

The FAA makes the following assumptions in deriving its cost estimates:

-   Average price per wing cover set: \$400

-   Each wing cover set would last, on average, five years.

-   Weight of a wing cover set: 10 pounds

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-   Operators would carry wing covers on the aircraft for each flight.

-   Incremental fuel burn for affected aircraft: 0.001 gallons per hour
    flown per pound of weight added

-   Each aircraft flies about 124 hours per year[^2]

-   Price of aviation fuel in Alaska: \$6.00 per gallon

-   Price of aviation fuel in the mainland U.S.: \$5.00 per gallon

*a) Alaska*

The cost of using wing covers in Alaska was estimated by adding the cost
of buying the wing covers to the additional fuel burn that would result
from carrying the wing covers back and forth on trips. It is assumed
that these wing covers would last for at least five years. As Table 4
below shows, there would be a cost of around \$155,000 (\$123,000
discounted) that would accrue to operators based in Alaska.

![](media/image3.png){width="6.4319444444444445in"
height="2.717361111111111in"}

*b) Mainland U.S.*

A similar analysis was performed for the mainland U.S. As Table 5 below
shows, there would be a cost of nearly \$9,400 (\$7,500 discounted).

![](media/image4.png){width="6.4319444444444445in"
height="2.748611111111111in"}

*c) Total cost*

As Table 6 below shows, if affected operators choose to comply with the
proposed rule by buying and using wing covers, the total cost of the
rule would be around \$164,000 (\$130,000 discounted).

![](media/image5.png){width="4.054861111111111in"
height="2.5909722222222222in"}

[Alternative 2: Delay Takeoff]{.underline}

Operators would also have the choice of delaying takeoff until the frost
melts from the aircraft. Operators who choose this method of compliance
may incur related costs such as the time value of delay and possible
loss of revenue due to canceled flights. Unfortunately, the FAA is
unable to estimate the cost of delay directly. The FAA would need
information on the number of flights delayed due to frost, but no such
measure is available. In addition, many of the affected operators
operate on demand, so for them, there may or may not be a delay cost,
depending on the nature of their business.

The FAA estimated the maximum cost of delay per plane per year such that
it would cost less to encounter delays than it would to buy wing covers.
The annualized cost over 10 years of using wing covers is estimated by
multiplying their discounted total cost (\$130,000) by the capital
recovery factor 0.14238. This gives an annualized cost of \$18,526.
Dividing by the total number of aircraft affected, 188, gives a total
annualized cost of \$99 per plane per year.

The FAA assumes the value of a passenger's time is \$37.20 per hour. If
an operator is transporting passengers, and if one passenger is delayed
as a result of this rulemaking, then waiting for the frost to melt would
cost less than using wing covers if an operator incurred delays of less
than 2.7 hours per plane per year. As the number of passengers
increases, the applicable delay length would decrease. For example, if
three passengers were delayed, the total annual delay would be about 54
minutes per plane per year. The FAA believes that operators who choose
to wait until frost melts completely from their aircraft are likely to
encounter delays much larger than those discussed here. Therefore, the
FAA expects that in most cases operators would find that wing covers are
a lower cost alternative.

The FAA realizes that many of the operators affected by this rule
transport cargo rather than passengers. The FAA cannot calculate a
specific "delay length" for these operators. However, if a delay as a
result of this rulemaking would result in more than \$99 in annual
losses per aircraft, the FAA believes that the operator would be better
off buying and using wing covers.

[Alternative 3: Store Aircraft in a Heated Hangar]{.underline}

Pilots and operators may also choose to mitigate the formation of frost
on their aircraft by storing these planes in a heated hangar. While this
may be possible when aircraft are being stored at a large hub airport,
smaller airports may not have hangars available at all. The average rent
for a heated hangar, where available, is about \$500 per month. The
annualized cost of wing covers is about \$99 per plane. In most cases,
the FAA expects that operators would find that wing covers are a
lower-cost alternative.

[Alternative 4: Deicing]{.underline}

The final alternative under consideration is deicing. Not all airports
have deicing facilities in place. At those airports that do have them,
the FAA estimates that deicing to remove frost would range from
\$60-\$100 per application. However, facilities vary in the deicing fees
they charge. Therefore, the FAA has calculated the maximum fee that an
owner or operator could pay per plane per year to remove frost by
deicing and be better off than he would if he bought wing covers. The
annualized cost of wing covers is about \$99. If the total annual cost
of deicing is less than \$99, then operators should choose to deice.
However, it is clear that having more than one deicing application per
year would cost significantly more. In most cases, the FAA expects that
operators would find that wing covers are a lower-cost alternative.

The FAA calls for comments on the cost estimates discussed above, and
requests that all comments be supported with clear and relevant economic
documentation.

## VI. CONCLUSION

Operators and pilots would have several alternatives to choose from to
deal with frost that may have accumulated on the wings of their
aircraft. After reviewing each alternative, the FAA recommends the use
of wing covers as the lowest-cost alternative. Assuming operators choose
to do so, over the ten year period from 2009 to 2018, they would incur
total costs of roughly \$164,000 (\$130,000 discounted). Of these,
\$155,000 (\$123,000 discounted) would accrue to Alaska, and \$9,500
(\$7,500 discounted) would accrue to the mainland U.S. Benefits total
roughly \$460,000 (\$320,000 discounted). About \$433,000 (\$301,000
discounted) in benefits would accrue to Alaska, while the remaining
\$27,000 (\$19,000 discounted) would accrue to the mainland U.S. Since
benefits exceed costs for both Alaska and the mainland U.S., the FAA
concludes the proposed rule is cost beneficial. The FAA calls for
comments on this determination and requests that all comments be
accompanied by clear and detailed supporting economic documentation.

## 

## 

## VII. APPENDIX: LIST OF POLISHED FROST ACCIDENTS, 1982-2007

![](media/image6.png){width="9.299305555555556in"
height="3.670138888888889in"}

  -------- ------------------------------------- --------------------------
  **\#**   **NTSB FINAL REPORT**                 **NTSB CAUSE REPORT**

  1        WHEN A WITNESS ARRIVED AT THE ARPT,    
           THE ACFT WAS AT THE FUEL PUMPS & THE  
           PLT HAD THE PREHEATER ATTACHED. THE   
           WITNESS RPRTD THERE WAS FROST ON THE  
           ACFT & THE PLT BRUSHED THE LOOSE      
           FROST OFF WITH HIS HANDS. THE PLT     
           ASKED FOR A WINDOW SCRAPER, WHICH WAS 
           PROVIDED, BUT THE WITNESS DID NOT     
           KNOW WHAT HE DID WITH IT. AFT         
           REFUELING, THE PLT STARTED THE ENG &  
           REMAINED ON THE RAMP A SHORT TIME BFR 
           TAXIING. A TKOF WAS INITIATED FROM    
           THE 5300 FT RWY IN CALM WND CONDS.    
           THE ELEV & TEMP WERE 9927 FT MSL & 2  
           DEG F. REPORTEDLY, THE ACFT ROLLED    
           FOR MORE THAN 3/4 OF THE RWY LENGTH   
           BEFORE BCMG AIRBORNE. THE WITNESS     
           RPRTD THAT AFTER LIFT-OFF, THE ACFT   
           DID NOT GAIN ALTITUDE, BUT REMAINED   
           LOW, BGN A LFT TURN, THEN WENT        
           DOWN.ANOTHER WITNESS OBSVD THE ACFT   
           FALL FROM A LOW ALT & CRASH IN A LFT  
           WING LOW ATTITUDE. A PAX RPRTD THE    
           PLANE SEEMED TO SLOW DWN & LOSE ALT   
           AFT TKOF, AS IF IT WAS TOO HVY.       
           HOWEVER, DISREGARDING ANY FROST/ICE,  
           THE ACFT WAS ESTIMATED 88 LBS BLO THE 
           MAX WT LMT. NO PREIMPACT, MECHANICAL  
           FAILURE WERE FOUND WITH THE AIRFRAME  
           OR ENG.                               

  2        ACCORDING TO FAA INSPECTORS, THE PLT   
           POLISHED THE LOWER LEADING EDGES OF   
           WINGS BEFORE DEPARTING, AS THEY WERE  
           COVERED WITH FROST. THE PLT STATED    
           THAT DURING CLIMB OUT THE ACFT        
           ENTERED AN INADVERTENT STALL,         
           FOLLOWED BY A THREE POINT LANDING     
           ONTO SOFT FIELD. THE ACFT FLIPPED     
           INVERTED.                             

  3        THE ACFT COLLIDED WITH A CAR DURING    
           AN ABORTED TAKEOFF. THE PLT SAID THAT 
           THE ACFT WOULD NOT ATTAIN FLYING      
           SPEED SO HALFWAY DOWN THE RWY SHE     
           ABORTED THE TAKEOFF. SHE ALSO SAID    
           THAT SHE AND HER PASSENGERS REMOVED   
           FROST OFF THE ACFT FOR ABOUT 25       
           MINUTES BEFORE THE ATTEMPTED TAKEOFF. 
           THE AIRSPEED INDICATOR NEVER MOVED    
           OFF OF ZERO AND SHE DID NOT ATTEMPT   
           TOGET THE ACFT OFF THE GROUND.        

  4        THE PLT RPRTD THERE WAS FROST ON THE   
           ACFT & THAT A ROPE HAD BEEN USED TO   
           SMOOTH IT OFF. HE THEN INITIATED A    
           TAKEOFF FROM A DRY LAKE BED. AFTER    
           LIFT-OFF, THE ACFT SETTLED BACK TO    
           THE GROUND & STRUCK A BERM AT THE END 
           OF THE TAKEOFF AREA.                  

  5        WHILE GETTING FUEL, THE PILOT OF THE   
           MOONEY M20C AND HIS 3 PALS WERE       
           ATTEMPTING TO REMOVE FROST WITH PAPER 
           TOWELS AND PLASTIC CREDIT CARDS AFTER 
           BEING TOLD BY THE FUEL TRUCK DRIVER   
           THAT THE ARPT HAD NO ICE REMOVAL      
           SOLUTION. A WITNESS STATED THAT AS    
           THE ATTEMPT WAS BEING MADE TO REMOVE  
           THE FROST & ICE, MORE FROST AND ICE   
           WAS FORMING. WITNESSES WHO OBSERVED   
           THE AIRCRAFT ON THE TAKEOFF STATED    
           THE ROLL WAY VERY LONG; THE CLIMB AND 
           TURNING BANK WAS STEEP; AND THAT THE  
           AIRCRAFT DESCENT ANGLE WAS STEEP. THE 
           ACFT COLLIDED WITH TREES AND BURST    
           INTO FLAMES.                          

  6        THE PLT RPRTD THAT BEFORE THE FLT,    FAILURE OF THE PILOT TO
           THE WINGS & STABILIZER WERE SWEPT,    REMOVE FROST FROM THE
           LEAVING A LAYER OF \'POLISHED\'       AIRCRAFT. CONTRIBUTING
           FROST. FREIGHT WAS LOADED & THE ACFT  FACTORS WERE: IMPROPER
           WAS SERVICED TO BRING THE FUEL LEVEL  WEIGHT AND BALANCE AND
           UP TO 120 GAL. AFTER START, TAXI &    SNOW COVERED TERRAIN.
           RUN-UP, THE PLT BEGAN HIS TAKEOFF     
           FROM THE APPROACH END OF THE 10,300   
           FT RWY (WITH 35\' MP & 2250 RPM). AT  
           ABOUT 100 FT AGL, HE ADJUSTED THE     
           POWER (TO 30\' MP & 2000 RPM) &       
           RAISED THE FLAPS TO CLIMB AT 82 KTS.  
           HOWEVER, THE ACFT DID NOT CLIMB &     
           WOULD NOT ACCELERATE IN LEVEL FLT.    
           THE PLT INCREASED THE POWER (TO 31\'  
           MP & 2100 RPM), BUT HE BELIEVED THERE 
           WAS A DEFINITE LOSS OF POWER.         
           SUBSEQUENTLY, THE ACFT WAS DAMAGED    
           WHEN THE PLT ABORTED THE TAKEOFF ON   
           SNOW COVERED TERRAIN BEYOND THE END   
           OF THE RWY. NO PRE-ACDNT PART FAILURE 
           OR MALFUNCTION OF THE ACFT OR ENG WAS 
           FOUND. AN INV REVEALED THE ENTIRE     
           ACFT WAS COVERED WITH A COATING OF    
           FROST. COMPANY RECORDS SHOWED THE     
           EMPTY WEIGHT OF THE ACFT WAS 5088     
           LBS; THE ACFT\'S ACTUAL EMPTY WEIGHT  
           WAS 5285 LBS. AN FAA INSPECTOR        
           CALCULATED THAT THE TAKEOFF GROSS     
           WEIGHT EXCEEDED THE MAX LIMIT BY 130  
           LBS.                                  

  7        THE PLT RPRTD THE ACFT SEEMED TO      FAILURE BY THE PILOT TO
           FUNCTION NORMALLY DRG THE TAKEOFF     ASSURE ADEQUATE REMOVAL OF
           ROLL; HOWEVER, AFTER LIFT-OFF, IT     FROST FROM THE AIRCRAFT
           WOULD NOT CLIMB ABOVE GROUND EFFECT.  WHICH RESULTED IN A
           HE SAID IT JUST CLEARED LOW TREES     STALL/MUSH.
           APRX 300 TO 400 FT FROM THE END OF    
           THE RWY, THEN IT STALLED INTO A       
           FENCE. NO PREIMPACT PART FAILURE OR   
           MALFUNCTION WAS FOUND. BEFORE THE     
           FLT, THE TEMP WAS SLIGHTLY BELOW      
           FREEZING &THERE WAS FROST ON THE      
           ACFT. A MECHANIC STATED THE FROST WAS 
           WIPED OFF THE WINGS & TAIL BEFORE THE 
           FLT. BEYOND THE DEPARTURE END OF THE  
           RUNWAY, THE TERRAIN WAS NOT SUITABLE  
           FOR AN ABORTED TAKEOFF. ALSO, THE PLT 
           RPRTD THAT THE FENCE \'SAVED THE      
           DAY\' AS THERE WERE SIGNIFICANT       
           OBSTRUCTIONS BEYOND THE FENCE.        

  8        THE CERTIFICATED COMMERCIAL PILOT,    THE PILOT\'S FAILURE TO
           WITH FIVE PASSENGERS ABOARD, WAS      REMOVE FROST FROM THE
           DEPARTING RUNWAY 18 ON A SCHEDULED    AIRPLANE PRIOR TO FLIGHT,
           COMMUTER FLIGHT. THE PILOT STATED     AND AN INADVERTENT
           THAT THE FLIGHT\'S ORIGINAL DEPARTURE STALL/MUSH.
           TIME WAS DELAYED FOR TWO HOURS DUE TO 
           ICE FOG, AND LOW VISIBILITY. HE SAID  
           THAT JUST AFTER TAKEOFF, THE ENGINE   
           SURGED FOLLOWED BY A LOSS OF POWER.   
           THE AIRPLANE COLLIDED WITH            
           SNOW-COVERED TERRAIN DURING AN        
           OFF-AIRPORT EMERGENCY LANDING, AND    
           SUSTAINED SUBSTANTIAL DAMAGE TO THE   
           PROPELLER, FUSELAGE, AND WINGS.       
           FOLLOWING RETRIEVAL OF THE AIRPLANE,  
           AN FAA AIRWORTHINESS INSPECTOR        
           EXAMINED THE AIRPLANE, AND FOUND NO   
           MECHANICAL ANOMALIES. WHILE STILL     
           ATTACHED TO THE AIRPLANE, THE ENGINE  
           WAS STARTED AND RUN AT IDLE. THE      
           ENGINE LATER PRODUCED FULL POWER ON   
           AN ENGINE TEST STAND. A PILOT-RATED   
           ALASKA STATE TROOPER, WITH EXTENSIVE  
           EXPERIENCE IN THE ACCIDENT AIRPLANE   
           MAKE AND MODEL, EXAMINED THE AIRPLANE 
           SOON AFTER THE ACCIDENT. HE SAID THE  
           WINGS, HORIZONTAL STABILIZER, AND     
           ELEVATORS HAD AN ACCUMULATION OF      
           FROST.                                

  9        THE PILOT TOLD THE NTSB INVESTIGATOR  THE PILOT\'S INADEQUATE
           DURING A TELEPHONE INTERVIEW ON       REMOVAL OF FROST FROM THE
           SEPTEMBER 2, THAT DURING HIS          AIRPLANE, AND THE
           PREFLIGHT HE NOTED FROST ON THE WINGS INADVERTENT STALL DURING
           AND TAIL SECTION OF THE AIRPLANE. HE  TAKEOFF. A FACTOR WAS WIND
           DESCRIBED REMOVING THE FROST WITH A   GUSTS.
           ROPE, AND HE BELIEVED HE HAD          
           ADEQUATELY CLEANED THE LIFTING        
           SURFACES. THE PILOT SAID THE AIRPLANE 
           CLIMBED TO BETWEEN FIVE AND TEN FEET  
           ABOVE THE OFF AIRPORT GRAVEL BAR, AND 
           THEN THE RIGHT WING STALLED. HE SAID  
           THE RIGHT WING STRUCK THE GROUND AND  
           THE AIRPLANE CARTWHEELED. THE PILOT   
           SAID HE BELIEVED FROST ON THE         
           AIRPLANE\'S WINGS CAUSED THE STALL.   
           THE PILOT WROTE IN HIS NTSB           
           PILOT/OPERATOR REPORT ON SEPTEMBER    
           10, THAT THE WINDS WERE GUSTY AT THE  
           TIME OF THE ACCIDENT. HE WROTE THAT   
           AS SOON AS THE AIRPLANE LIFTED OFF, A 
           GUST \'CAUGHT THE AIRCRAFT AND FORCED 
           THE RIGHT WING DOWN.\' THE AIRPLANE   
           SUSTAINED SUBSTANTIAL DAMAGE TO THE   
           RIGHT WING, TAIL ASSEMBLY, AND        
           EMPENNAGE.                            

  10       THE PILOT REPORTED THAT DURING THE    THE PILOT\'S FAILURE TO
           PREFLIGHT HE NOTED ICE AND FROST      ADEQUATELY REMOVE
           ADHERING TO THE AIRPLANE. AFTER       ICE/FROST FROM THE
           APPLYING GLYCOL HE POLISHED AND       AIRCRAFT AND TO MAINTAIN
           BRUSHED OFF THE FROST. THE PILOT      AIRSPEED DURING THE
           WARMED UP THE ENGINES BEFORE TAKING   INITIAL CLIMB AFTER
           OFF TO STAY IN THE PATTERN \"TO CLEAR TAKEOFF. AN INADEQUATE
           THE AIRPLANE OF THE ICE, AND TO MAKE  PREFLIGHT WAS A FACTOR.
           SURE EVERYTHING WAS WORKING           
           PROPERLY.\" BEFORE RELEASING THE      
           BRAKES, THE PILOT BROUGHT THE POWER   
           UP TO MAKE SURE EVERYTHING WAS IN THE 
           GREEN. THE PILOT STATED THAT FOR      
           TAKEOFF, HE \"TRIED TO BABY THE       
           ENGINES USING A LESS THAN MAX POWER   
           FOR THE DEPARTURE.\" THE TAIL OF THE  
           AIRPLANE CAME UP ABOUT 3/4 OF THE WAY 
           DOWN THE RUNWAY. SEEING THE END OF    
           THE RUNWAY, MORE POWER WAS ADDED AND  
           THE AIRCRAFT LIFTED OFF. THE LANDING  
           GEAR WAS RAISED WHEN A POSITIVE RATE  
           WAS ATTAINED. SHORTLY AFTER GEAR      
           RETRACTION THE PILOT STATED THAT, \"I 
           FELT THE AIRPLANE MUSHING, LIKE A     
           STALL. I THEN ADDED MORE POWER, BUT   
           THE AIRCRAFT KEPT MUSHING, AND THEN   
           IT IMPACTED TERRAIN WITH POWER ON     
           BOTH ENGINES.\" THE AIRCRAFT CAME TO  
           REST IN AN OPEN FIELD LOCATED         
           APPROXIMATELY 1/4 MILE FROM THE END   
           OF THE RUNWAY. AFTER THE ACCIDENT,    
           ICE WAS STILL NOTED ADHERING TO MOST  
           OF THE AIRPLANE.                      

  11       THE PRIVATE CERTIFICATED PILOT WAS    THE PILOT\'S INADEQUATE
           DEPARTING UPHILL FROM A 1,950 FEET    REMOVAL OF FROST FROM THE
           LONG RUNWAY ON A TITLE 14, CFR PART   WINGS, AND HIS FAILURE TO
           91 LOCAL AREA PERSONAL FLIGHT. THE    ATTAIN ADEQUATE AIRSPEED
           PILOT INDICATED THAT PRIOR TO         DURING TAKEOFF INITIAL
           DEPARTURE, THE UPPER WING SURFACES OF CLIMB, WHICH RESULTED IN A
           THE AIRPLANE HAD A LAYER OF FROST,    STALL AND COLLISION WITH
           BUT HE SMOOTHED THE SURFACE WITH A    TERRAIN. FACTORS
           BROOM. DURING THE TAKEOFF ROLL, THE   CONTRIBUTING TO THE
           PILOT SAID THE AIRPLANE BECAME        ACCIDENT WERE THE PILOT\'S
           AIRBORNE IN GROUND EFFECT TO AN       DELAYED ABORTED TAKEOFF,
           ALTITUDE OF ABOUT 2 FEET, ABOUT 300   AND AN INADVERTENT STALL.
           FEET BEFORE THE END OF THE RUNWAY.    
           THE AIRPLANE STALLED AND COLLIDED     
           WITH ALDER BUSHES ABOUT 75 FEET       
           BEYOND THE END OF THE RUNWAY. THE     
           AIRPLANE RECEIVED DAMAGE TO THE       
           WINGS, FUSELAGE, AND ENGINE.          
  -------- ------------------------------------- --------------------------

[^1]: §§91.527 (a)(3), which falls within Part 91, Subpart F, provides
    for the operation of large and turbine-powered multiengine airplanes
    and all fractional ownership program aircraft (regardless of
    category, class, weight, powerplant or number of engines).
    Therefore, the revised provisions in subpart F in this proposed rule
    would affect the operation of all fractional ownership program
    aircraft under subpart K. The FAA has reviewed the Management
    Specifications for part 91 K operators and has found that no part 91
    subpart K operator has an authorized deicing program that
    incorporates the polished frost procedure. Also, operators of
    smaller general aviation aircraft would not be affected by this
    rulemaking. As a result, the scope of this analysis was limited to
    Part 125 and 135 operations.

[^2]: In Alaska, 74% of the affected aircraft are single-engine
    aircraft, 21% are twin-engine, and 5% are piston rotorcraft. The 124
    hours comes from the weighted average of the standard hours flown by
    aircraft type used by APO: 0.74 x 112 + 0.21 x 143 + 0.05 x 226 =
    124 hours. The FAA assumes this statistic is similar for aircraft
    used in the mainland U.S.