Clip4
Touchdown! Greaser!
thank goodness I don’t have to clean bugs off in winter.
How much frost...
- Thread starter Jim K
- Start date
thank goodness I don’t have to clean bugs off in winter.
Snowmass
Line Up and Wait
I am very familiar with 400 and 600 grit sand paper (painted my planes and many cars)and it is a LOT smoother than grains of salt. Salt would be like 40 grit.
Ryan F.
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Ryan Ferguson 1974
Let's be very clear here -- the legal answer is zero frost. The safe answer is also zero frost. ZERO.
While it may have worked for you "this time" the difference between very minute amounts of frost can add up to a huge lift and drag penalty. This is a lesson the industry has learned in such a way that the regulation is inked in blood.
This truly is nothing to mess around with. I implore all reading this thread to take this subject very seriously. Zero contamination is the only way to fly!
While it may have worked for you "this time" the difference between very minute amounts of frost can add up to a huge lift and drag penalty. This is a lesson the industry has learned in such a way that the regulation is inked in blood.
This truly is nothing to mess around with. I implore all reading this thread to take this subject very seriously. Zero contamination is the only way to fly!
Clip4
Touchdown! Greaser!
Sorry Mr Examiner, nothing in the regs says zero frost.
Even 91.527 does not require all frost to be removed. a) No pilot may take off an airplane that has frost, ice, or snow adhering to any propeller, windshield, stabilizing or control surface; to a powerplant installation; or to an airspeed, altimeter, rate of climb, or flight attitude instrument system or wing, except that takeoffs may be made with frost under the wing in the area of the fuel tanks if authorized by the FAA
The logic and rationale that some of you have is what amazes me.
Doc Holliday
En-Route
Mr. Puppy Mill Instructor,
How about applying some common sense. Good ADM and RM would dictate a clean wing. Anything above that and you are becoming a test pilot.
The stall aoa would remain the same. The airspeed you need to maintain to stay below that aoa becomes the question. A 10% increase in stall speed in my plane would be 5 knots...
Ryan F.
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Ryan Ferguson 1974
That is indeed the regulation I am referencing. The original poster mentioned a small amount of frost on the wings. The allowable amount is zero. As a result, I don't see any need to amend my statement.
MauleSkinner
Touchdown! Greaser!
A small amount on a small airplane. No reg addresses it.
Clip4
Touchdown! Greaser!
For the newer pilots here, the FAA allowed polishing frost smooth until just 10 years ago. The problem was people trying this on laminar flow wings and no definition of what constitutes smooth.
From 1984-1992 the NTSB identified only 8 accidents that could possibly be identified as pretakeoff frost or snow on aircraft accidents - 1 a year. In 2009 the FAA standardized it’s recommendation that frost be removed. In more modern aircraft such as Cirrus, the POH prohibits takeoff with ice, frost or snow on the aircraft thus making removal regulatory under FAR 91.9. Below are some historical links if interested.
https://www.federalregister.gov/doc...al-of-regulations-allowing-for-polished-frost
https://www.faa.gov/other_visit/avi...afety/safo/all_safos/media/2006/safo06014.pdf
https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_135-17.pdf
https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC135-17.pdf
From 1984-1992 the NTSB identified only 8 accidents that could possibly be identified as pretakeoff frost or snow on aircraft accidents - 1 a year. In 2009 the FAA standardized it’s recommendation that frost be removed. In more modern aircraft such as Cirrus, the POH prohibits takeoff with ice, frost or snow on the aircraft thus making removal regulatory under FAR 91.9. Below are some historical links if interested.
https://www.federalregister.gov/doc...al-of-regulations-allowing-for-polished-frost
https://www.faa.gov/other_visit/avi...afety/safo/all_safos/media/2006/safo06014.pdf
https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_135-17.pdf
https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC135-17.pdf
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Stewartb
Final Approach
Some of you guys with ZERO experience ought to step back and examine your positions. What makes you so sure about something you know nothing about?
Clip4
Touchdown! Greaser!
And here is what our Canadian neighbors say.
https://www.tc.gc.ca/eng/civilaviation/publications/tp185-3-05-general-706.htm
https://www.tc.gc.ca/eng/civilaviation/publications/tp185-3-05-general-706.htm
Stewartb
Final Approach
Ya know where the hardest place is to remove frost and ice? It's around the VGs. You know, those little raised blades we purposely install to interrupt airflow on our leading edges to improve lift. 
Snowmass
Line Up and Wait
And testing is how we actually KNOW as opposed opposed to opinions. As an aero engineer I love testing.
Stewartb
Final Approach
EVERY builder of an e-ab airplane is a test pilot. We have PPLs to qualify us. It's more fun than a barrel of monkees. At least for those of us who've done it. Want the REAL expert opinions? Ask someone who hasn't. They know it all!
PaulS
Touchdown! Greaser!
Lol, I'm gonna frost up my airplane to make a stol.
Stewartb
Final Approach
You'd know more than you do now. That's a start.
Lachlan
En-Route
After reading this thread, I've learned the following:
If your name is Ryan, you won't mess with frost. None. Zero.
If you're name is something different, you might, you might not, maybe you have, maybe you just did...
If you *ALREADY* flew with frost on your airframe, and you're here to tell about it, you may be an idiot who is lucky to be alive, or you may be a handsome test pilot.
Either way, we're all aviators. We're all pals. Be cool. Stay frosty.
If your name is Ryan, you won't mess with frost. None. Zero.
If you're name is something different, you might, you might not, maybe you have, maybe you just did...
If you *ALREADY* flew with frost on your airframe, and you're here to tell about it, you may be an idiot who is lucky to be alive, or you may be a handsome test pilot.
Either way, we're all aviators. We're all pals. Be cool. Stay frosty.
MauleSkinner
Touchdown! Greaser!
I’m an idiot and lucky to be alive, and flying with frost on the wings doesn’t even come near making the short list of defining moments.
It always makes me laugh when someone posts a message like this. I take it you know each of our qualifications and what experience we do or do not have?
Sounds like a bold assumption toward individuals that you know nothing about.
Stewartb
Final Approach
Speak up. What exactly is your experience with frosted wings? I've been honest with mine.
EdFred
Taxi to Parking
Planes with a fat wing, I'm not worried about a little bit of frost. Laminar flow wings, I'm a lot more cautious. Since I'm not bound by the quoted reg, I will continue to make decisions to go/no go based on my first hand experience. I'm also not going to listen much to a guy from Florida about cold weather flying.
Clip4
Touchdown! Greaser!
Don’t be bashing those Florida guys, the frost gets the citrus crop down there about once a decade.
February 2017, visited uncle in Rio Rancho, New Mexico who flies a 310. Got to the airport about 6:30a to pre-flight and the airplane had a nice layer of frost on the control surfaces. Left and waited until the mid-morning sun melted it off.
All of the airplanes I fly are hangared, so I don’t have to deal with this issue on a regular basis.
I guess this doesn’t count as ‘experience’ in your book, since we weren’t dumb enough to takeoff like that and see if it would fly or not.
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Stewartb
Final Approach
Not experience. You got that part right. Not a valid opinion is what you need to come to grips with.
Por que no los dos?
Half the people in this thread should be dead according to the other half. OP was gracious enough to already search the NTSB database and made a most astute observation - all of the accidents that involve frost, while frost was a factor, was not the sole reason of the accident.
Clip4
Touchdown! Greaser!
You better have a psychiatrist on standby in case you ever end up in a little un-forecast rime and have to deal with it.
Tantalum
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San_Diego_Pilot
and then we had a guy here a few years ago talk about flying his Arrow into icing conditions and not noticing any performance degradation even with an inch of ice in the wings..
it is surely dumb and in my opinion ice is not to be messed with in any capacity even if that means just frost, but surely there are people that do
it is surely dumb and in my opinion ice is not to be messed with in any capacity even if that means just frost, but surely there are people that do
Tantalum
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By the way, how do commercial airliners know whether there is ice or not? I saw a pirep the other day near Flagstaff of s A320 reporting moderate time at 14000
I've done plenty of flying commercial planes in the winter snow and moisture and I've never noticed any ice anywhere on the wings.. the pilots notice it on the windshield or something? Curious
I've done plenty of flying commercial planes in the winter snow and moisture and I've never noticed any ice anywhere on the wings.. the pilots notice it on the windshield or something? Curious
Tantalum
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The most horrifying element about ice in my experience has been how quickly it builds on the wings.. within a minute or two you can have a serious problem on your hands
So, by your logic, in order for one to have ‘experience’ they have to place themselves in potentially fatal situations... and without having done so, they are forbidden to advise others against making such a mistake? Most people with common sense would disagree with your rationale.
The fact of the matter is there are people here who have dealt with frost for a very considerable amount of time. I don’t think anyone here is saying that it’s a *good* idea to go blasting off with frost on your wings, just that it’s not nearly as inherently reckless or deadly as some are making it out to be.
Lets recap: Great idea? No. Guaranteed instadeath? Also no.
AKBill
En-Route
I didn't think you could over load a Caravan..
Looks like frost in Juneau. Boy it can really get thick.
Stewartb
Final Approach
experience would imply experience. Anything less is fiction.
AKBill
En-Route
I'm in the remove the frost if you can, smooth it out is a must
jspilot
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jspilot
Here’s the thing— you won’t know it’s unsafe until it’s too late and you are stalling and then spirallling down towards death. As pilots we don’t get to “guess and check.”
Being a renter pilot up here in the Northeast where planes are stored outside, I’ve had my fair share of frost related delays/cancelations over the years. One of the things that makes the OP’s decision a little bit less safe is the choice to take off at night with frost as, usually frost will melt with full sun even in the dead of winter. Taking off at night does not give him that option. I’ve always been taught that frost on the wings or control surface is a no go— does not matter the type, amount, safety flexibility, whatever other justification someone might use— it’s a no go. I see a lot of people saying they have flown with frost and gotten away with it but I really am struggling to understand why they are thrusting an unsafe practice into this conversation and advocating “just because I can do it so should you” (paraphrasing here.). We should be trying to advocate safe piloting decisions and not borderline unsafe decisions like flying with frost. The aviation community is different from other communities because we take safety very seriously and live( or die) with every decision we make.
Last winter I asked a similar question on here about a patch of frost I caught before taking off that was left on the fuselage by the line guys. I had them remove the frost and the concensous amoungst those who responded to that thread was “better to play it safe with frost.”
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Katamarino
Pattern Altitude
Just make sure there's less than this, and you're good to go.
timwinters
Ejection Handle Pulled
Owwwwwwwww!
This seems to be the thought process by many, but I would argue while true with structural icing, it's just not the case with frost. The condition exists on the ground. You accelerate the airplane and see if it rotates and flies as normal. If not, you set it back down-unless you took off from a very short runway, which is the case in most of the accidents, or you panick and try to force it to fly when it doesn't want to, which pretty much covers the rest.
I don't disagree with the sentiment that you should clean the wing completely. Without getting too far off in the weeds, I was already behind and my choices were scrape the wings with a credit card, or wait a couple hours for the line guys to finish turning a 737 and help me. I am well aware that narrative sounds hauntingly like the beginning of an ASI video, which is what spurred me to start this thread.
If the shape, weight, and smoothness of the wing are minimally changed, what makes frost different from paint? That's a genuine question. I just haven't found evidence or even a convincing argument that it's not a manageable risk with lots of runway and an understanding of how your aerodynamics may be effected. It's plausible that smooth frost might have a higher coefficient of friction than paint.
For what it's worth, by the time I got home the frost had sublimated off.
Why take any risk at all? That's a valid point. In my mind flying a piston single at night was by far the biggest risk I took.