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Re: Low-flap landing, at high speeds (150+kias)

Posted: 23 Feb 2012, 13:18
by Garry Russell
:lol: :lol: :lol: :lol:

If you expected a simple "Ye"s or "No" you may have been surprised :)

Gives a chance for a few fact to come out from the woodwork

Happy flying

Re: Low-flap landing, at high speeds (150+kias)

Posted: 23 Feb 2012, 15:15
by MALTBY D
I suppose a lot could depend on if you're using autopilot.
If you are on A/P and you select flaps late, it can mess your altitude about.
However if you are flying manually, following the ILS, it's easy to anticipate the effect of flaps and quickly null it out.

Just to add a bit more - By the time of the 1-11, things were slightly different and you wouldn't get behind the power curve with full flaps.
In fact American Airlines procedure for landing was to select full flaps at Vat+20, just before intecepting the glide slope.
No problems like the Comet for the VC10 & Trident either.

DM

Re: Low-flap landing, at high speeds (150+kias)

Posted: 23 Feb 2012, 15:44
by Garry Russell
I would have thought a Comet with full, almost vertical flap would be in trouble. :worried: *-)

The Viscount was often on crossing the threshold or after touchdown to aid braking. Typically, locally it was at about a quarter mile to bring it right down for a touchdown on the piano keys....on a longer runway crossing the threshhold would still mean a little way to go for a comfortable touchdown further down the runway

Whatever the differences or the reasons between types, they are laid down in the pilots notes and that is what is done or at least should be :lol:

Of course it could be argued that in Flight Simulator it doesn't matter and although that is true, there is a demand for accuracy and that is something we strive to achieve :)

The difference between a simulator and a game in effect :)

Re: Low-flap landing, at high speeds (150+kias)

Posted: 23 Feb 2012, 16:31
by DaveB
I'm getting confused :doh: :lol:

I've always understood the full flap setting on the Comet was used as you crossed the fence. I don't like doing that in FS as it unsettles the aircraft too much and landing is difficult enough as it is :lol:
ATB
DaveB B)smk

Re: Low-flap landing, at high speeds (150+kias)

Posted: 23 Feb 2012, 17:44
by MALTBY D
Full flap on the Comet is optional and is best used within 1 nm of touchdown.
If you select full flap too early on approach you will most likely cause yourself problems with lack of speed and power.

I may have caused some confusion with the phrase...
No problems like the Comet for the VC10 & Trident either.
There were no problems for the VC10 & Trident. No problems like the Comet had.

Does this make sense? :lol:

DM

Re: Low-flap landing, at high speeds (150+kias)

Posted: 23 Feb 2012, 17:46
by Garry Russell
That does :lol:

Re: Low-flap landing, at high speeds (150+kias)

Posted: 24 Feb 2012, 09:09
by guym-p
DaveB wrote:I've always understood the full flap setting on the Comet was used as you crossed the fence. I don't like doing that in FS as it unsettles the aircraft too much and landing is difficult enough as it is :lol:
From the RAF Pilot's Notes for Comet C. Mk. 4c (A.P. 4681 D-P.N./1) which is more descriptive than the de Havilland/BOAC Flying Manual on this:

"After lining up on final approach, slowly reduce to and maintain the 40º flap approach speed. At about 600 feet, but not normally below 400 feet, lower the flaps to 60º and allow the speed to reduce slowly to achieve the 60º flap Final Approach Speed at the runway threshold. At the threshold, lower the flaps to 80º and reduce power to the correct Target Threshold Speed. The lowering of the final amount of flap will assist in the dissipation of the 5 knots difference between the Final Approach and Target Threshold Speeds and the slight nose-up change of trim assists the round-out."

It appears many pilots considered this last flap position optional. Roger Beazley, who piloted Comet XV-814 during its round the World tour in 1992, used only 60º flap. Peter Duffey, BOAC training captain for the Comet 4, used full flaps, and wrote: "The ground cushion was substantial allowing the usual soft arrival".

Many other pilots write about the extremely soft landings that were possible with the Comet, but in wet conditions it could lead to aquaplaning, and pilots had to fly the aircraft onto the runway more deliberately to make a firm landing.

Guy.

Re: Low-flap landing, at high speeds (150+kias)

Posted: 24 Feb 2012, 10:25
by DaveB
Thanks for that Guy :thumbsup: I much prefer to be setup earlier.. thank goodness flightsim doesn't simulate aquaplaning! :lol:

ATB
DaveB B)smk

Re: Low-flap landing, at high speeds (150+kias)

Posted: 24 Feb 2012, 11:30
by Garry Russell
:lol: :lol: :lol: :lol:

If it did Dave you could re introduce HS.748 flights into Portsmouth :worried:

Re: Low-flap landing, at high speeds (150+kias)

Posted: 24 Feb 2012, 11:47
by DaveB
:lol: :lol:

I'm not sure if tundra tyres or just plain skids would be better there mate :lol: Much easier to fly a Twinpin in.. turn it into the wind and land vertically :lol:

ATB
DaveB B)smk