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TotalBeginner
29th Jan 2006, 20:37
Whenever I visit an unfamiliar aerodrome, I always forget to ask someone where they normally perform their power checks.

Last week I visited an airfield, and after requesting taxi information, I asked politely where I should perform my power checks. The AFISO said that as they weren't busy, I should backtrack the runway, line-up and perform the checks there.

After doing so I was asked to expedite due to traffic positiong for a stright in.

Has anybody ever had similar problems? I've also been to some airfields where the taxiway is too narrow to turn away from parked aircraft, or even into wind.

Genghis the Engineer
30th Jan 2006, 00:21
As a general rule, if there's nowhere set-aside for the purpose, pull off to the side of the taxiway a short distance prior to the entering the runway and do it there.

As an absolute rule, if told to expedite before you have confirmed that the aircraft is fit for flight, refuse. If to remain on the runway would potentially cause an accident (which it certainly wouldn't have done here), go off the side of the runway - but that is still preferable to flying without having completed your pre-flight checks and engine run-ups.

"Unable to comply, conducting engine run-ups on the runway as you advised sir". Emphasis on the sir!

G

Genghis the Engineer
30th Jan 2006, 00:24
As a general rule, if there's nowhere set-aside for the purpose, pull off to the side of the taxiway a short distance prior to the entering the runway and do it there.

As an absolute rule, if told to expedite before you have confirmed that the aircraft is fit for flight, refuse. If to remain on the runway would potentially cause an accident (which it certainly wouldn't have done here), go off the side of the runway - but that is still preferable to flying without having completed your pre-flight checks and engine run-ups.

"Unable to comply, conducting engine run-ups on the runway as you advised sir". Emphasis on the sir!

G

Talkdownman
30th Jan 2006, 05:37
Emphasis on the sir!
Nah. We don't wanna give FISOs delusions of grandeur. That's reserved for the ATCOs.

A and C
30th Jan 2006, 06:48
Its high time that people stopped making incredably tight turns on small taxiways to turn onto wind to do the power checks all you manage to do is scrub the tyres and may be run off the taxiway or hit another aircraft when trying to point the aircraft back towards the runway.

Most modern light aircraft simply DO NOT need to face into wind to do the power check but a tail wind is not a good idea so as long as the aircraft is crosswind or nose slightly into wind that is OK.

The aircraft should be positioned so that the prop wash is directed into a clear area, cross wind will not have any effect on engine cooling that you can mesure.

Tail draggers are a different story and into wind is a very good idea except in the very lightest breeze.

I agree with posts above that say you should not normaly do the checks on the runway but how long did you take ? if you are new to flying or have not flown for a wile then say so and stay clear of the runway because you know that it will take you a little longer to do the checks but if you are fully up to speed it is a different matter.

I expect that I will get a slagging from the "airmanship" brigade but they are the same people who are not leaning an engine below 6000 ft !

dirkdj
30th Jan 2006, 10:42
Actually, facing downwind (tail into the wind) is the best position for engine cooling on the ground. This effect can be clearly seen on engine analysers that show the CHT for every cylinder.

With a tailwind the propeller (at idle or low power) has a greater angle of attack than the same prop in headwind conditions where it could be 'freewheeling' with no added cooling effect.

Worst position is crosswind.

No need for long ground runups at high power in my opinion.