Defrost before flight

Brian Hope · Post by **Brian Hope** » Mon Jan 05, 2009 11:55 am

‘DEFROST THOROUGHLY BEFORE USE’,
CAA URGES ACTION ON DE-ICING AIRCRAFT

The UK Civil Aviation Authority (CAA) has issued a seasonal appeal for pilots and ground crew to not underestimate the dangers posed to aircraft of ice and ground frost this winter. As temperatures continue to drop, commercial aircrew, maintenance staff and general aviation pilots should take the job of de-icing aircraft very seriously. Ultimately, an aircraft should never take-off with any form of contamination on its wings, particularly ice, snow and frost (although some types may be permitted some frost on lower wing surfaces).

The CAA advises pilots in particular to take the free online course available on the NASA website: http://aircrafticing.grc.nasa.gov/courses.html. The course has been developed by an international team of professional pilots and experts in de-icing fluids and training applications. It discusses the risks of contamination, cues to alert the pilot to ground icing hazards, and actions to help ensure safe operations. Imagery, case studies, pilot testimonials, and interactive elements are used to inform the pilot and help him or her make better operational decisions.

Captain Graham Stokes, a Flight Operations Inspector at the CAA, said: “We want to ensure that staff who have anything at all to do with de-icing an aircraft take the task very, very seriously. Flight crew and ground staff need to work together as a team and training needs to be delivered properly.”

In 2002, the official investigation into the crash on take-off of a corporate jet at Birmingham International Airport identified an iced-up wing as the cause. The Air Accidents Investigation Branch concluded that the Bombardier 604’s fatal roll moments after take-off ‘had resulted from the left wing stalling at an abnormally low angle of attack due to flow disturbance resulting from frost contamination of the wing’. All five passengers and crew were killed.

Jim Gale · Post by **Jim Gale** » Mon Jan 05, 2009 3:12 pm

And it happens to fabric covered wooden structures as well! Picked up some ice last Saturday, late in the day. Had watched the wings as I descended from the clear blue down through the haze but could see no indication of ice until I got out of the aircraft at the pumps, only to find several very small lumps of ice on the tailplane. The runway was hard with no puddles/wetness.
Why on the tail and not the main wing?
Safe flying.
Jim.

Bob F · Post by **Bob F** » Mon Jan 05, 2009 7:19 pm

Brian & Jim,

Brian,

Thanks for the link, looks good although I have just bookmarked it at the moment.

Jim,

Was your tailplane iced up on both sides, or one more than the other? Interesting point you make, although someone is bound to come up with an answer for you

cardiffrob · Post by **cardiffrob** » Tue Jan 06, 2009 7:39 am

I landed a 757 at Innsbruck just before christmas. No signs of ice visible from the front (we usually see bits building up on the windscreen wipers) but I discovered about 2 inches on the leading edges after landing.....'cos it dropped onto my head during the walkround. Darned dangerous stuff, that ice.

Jim Gale · Post by **Jim Gale** » Tue Jan 06, 2009 12:00 pm

The little lumps of ice were on the starboard tailplane.
Might part of the explanation be that we had departed from a grass airfield 40 minutes earlier, although on my walk round prior to taking off I did not notice any moisture/frost accretions especially as I had been particular in parking the aircraft tail into full sun so as to get the best warming effect possible.
The only other observation noted was that another Jodel landed just before me and it was parked outside for about 20 minutes before the owner put it away in the hangar. By that time frost had started to form on the upper surfaces, so perhaps there was just a bit more moisture in the air at our local airfield.
Jim.

Steve Brown · Post by **Steve Brown** » Tue Jan 06, 2009 12:34 pm

Perhaps there was a lot of hot air coming from the preceding Jodel or its owner that condensed out and froze on your tailplane.

If it was fairly right wing invective (understandable in current times), maybe that's why it was only on the starboard side.

Only having fun - no offence meant Brian or to any of your clan.

Brian Hope · Post by **Brian Hope** » Tue Jan 06, 2009 1:17 pm

No offense taken Steve, and you are certainly right about the right wing hot air.

Bob F · Post by **Bob F** » Tue Jan 06, 2009 7:28 pm

Jim,

Is your engine a Right or Left tractor? I just find your observation interesting and wonder if the prop generated airflow around the fuselage may have had something to do with the formation on one side, and the lack of it on the other.

Jim Gale · Post by **Jim Gale** » Tue Jan 06, 2009 10:15 pm

Bob. Std 0-200 turning clockwise sitting behind it.
Regards, Jim.

Steve Brown · Post by **Steve Brown** » Tue Jan 06, 2009 10:28 pm

It was honestly only just a few plays on words which was intended to make readers smile. ('Hanger Chat - Come on in for general chat and POLITE banter between LAA members')
I'm genuinely sorry if anyone takes offence - it was not meant personally.