The other day in KTT on a very cold clear day, each aircraft, which included a selection of uk charter guys and Finnair a/c, got de iced prior to departure. This being to remove the build up of frost and ice which develops very quickly at -20. Then all of sudden a JMC a/c departs after a longer turn around than most, without deicing, thus saving £400+.

Whilst it was cold and clear, with no snow deposits, was he being practical and us wasteful, or him the cowboy and us professional.

It was my decision to deice and seeing the Finnair who has far more cold weather ops experience follow suit provide reassuance of a good decision.

If rumours are to be believed then of all the operators on the ramp his company is maybe the most finnancially insecure, I hope this did not play any part in his decision making process.

Guys thanks for the great advive , I originally posted this question on a friends PC , as BUSH . Feel relieved , have printed the pages . all great advice and i would like to thank you all very much .

None Nil yilch....your engineers should know better. We are trained in this and believe me it is NIL.....BA have a wonderful CD ROM on this I am sure there are copies around it is good for boith ground and flt crew use. See if you can get a copy.

Showed up one cold day to pick up a C-172, then fly to another airport to pick up some friends to fly to still another airport and found the a/c covered in frost. Spent a couple hours thoroughly scraping the frost off between rivet lines and had an interesting moment discovering climbout required considerably more pitch while having a low level look at the convenient creek bottom thoughtfully placed at the end of the runway. <img src="eek.gif" border="0">

After that I kept a couple extra jugs of automotive windshield deice fluid and a good squeegee/sponge combo in the car because no way am I taking off an a/c unless the wings SPARKLE.

In another vein, I checked with the Wardair chief pilot after witnessing an A310 take off with frost over the wing tanks because of cold-soaked fuel. Turned out that Airbus had done flight testing and had approvals for that operation.

Just a minor point, are you aware that Aeroshell Compound 6 (De-Ice) is now £4 per Litre plus vat.
Anyone know of a chemical supplier of
isopropyl alcohol in 25 Ltr drums, this being the main constituent.
regards

Ddon't know if you think this relevant but I once saw a Dung Duster (Agricultural Fertilser Spreader) that was parked at the time. The Horizontal stabiliser, it was a tail dragger, was caked with at least an inch of mud on 90% of the leading edge. The acft had obviously flown in this condition, from memory it was a Pawnee, perhaps they are a very forgiving acft.

The point is its not just ice that will affect the aerodynamic efficiency of your acft, but any for of solid contamination.

My companies Ops Manual and other winter ops documents used to explicitly state a "Clean Aircraft policy". In other words, no contamination allowed.

Lately however this has gradually been diluted. The old mantra no longer appears in the books, and most operators manuals (jet types) allow up to 1/8th inch of 'hoar frost' on the fuselage as acceptable. They even suggest that if you can read the logos on the fuselage through the ice then you have around 1/8th inch contamination...and can go.

Personally I don't feel comfortable with this and I insist on a clean aircraft. Among the reasons...if you have contamination on the top of the fuselage you probably have it on top of the wing too!
It only takes a few minutes more to spray the fuselage, but I still get funny looks from engineers and even some F/O's who are quick to remind me what th book allows as acceptable!

The difficulty is that many other skippers accept this level of contamination...including training Captains. Makes it a lonely path to tread at times, but still less lonely than the graveyard.

Good point Idunno

some days ago in Turin (coming from a long flight at FL330)cold fuel was creating a widespread hoar frost on the upper wings (spreading to the ailerons).I was behind schedule for the next leg. Nevertheless i added another 10 minutes of delay to get the wing deiced. Whether necessary or not didn't matter!

B_D

STEAMHEAD
WAS A COMPANY, ELLIS & EVARARD, 0208 858 5808 OR 01962 864446 SELLING BULK CHEMICALS.
TWO CAVEATS, 1)MAY NOT BE THAT SIMPLE A CHEMICAL FOR AIRCRAFT
AND 2)MAY NEED A CUSTOMS PERMISSION TO BUY AN ALCAHOL IN BULK.

A couple of points in our Winter Operation handbook.

A light sandpaper roughness on a leading edge can reduce lift by 18%.

As little as one half inch of ice can reduce aircraft lift by 50%.

I also have been called a pussy in the past but never ever departed with ice or snow on the aircraft.

Well done young man. Any ice on an airplane is too much. Another old pilot once told me "the only place for ice in an airplane is inside a large whiskey." Good advice. Heard a story recently about a Captain who refused to put on the wind anti-ice when the windscreen was covered in the stuff. Co-pilot had to force him to do it. Any more info on that? If true what a prat and a dangeroud one too.

Legolas, don't tar us all with the same brush, ask the crew who didn't want their a/c de-iced tonight even though I said it required it and refused to release the a/c until it was de-iced.

Bush-I think most of what needs to be said has been on this subject. I would just like to add that if airoplanes where meant to have any crinkly rough surfaces then someone would have built them that way-no good eng would offer a kite for service with any contamination and no good pilot would take it-its also interesting to note that some 80 percent of quality reports I saw from this period last year with an airline I know refered to deicing being carried out incorrectly - know your subject -Kilfrost do some good training vidoes etc.