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Vx and Vy - almost completely useless?

Full flaps? On takeoff? That’s a new idea I think…

Well, it does make the take-off roll shorter. On my practical test for my license, I took off with the FK9’s flaps at the first ‘tooth’ as I learned at the club; the examiner was not dissatisfied, but he did make me repeat the take-off with full flaps, and lift-off occurred noticeably earlier. I have since tried the same test on my own pride and beauty, with the same result. Of course these machines come airborne at some 80-90 km/h, perhaps not a good comparison to the average Cessna/Piper, let alone higher performance planes.

To keep things in perspective: the change might well be from 100 metres to 60, until lift-off…

Last Edited by at 22 Mar 20:01
EBZH Kiewit, Belgium

Full flaps? On takeoff? That’s a new idea I think…

Depends on a/c type. For my plane (Socata ST-10), the POH recommends full flaps (30 degrees) for short field operations.

LOAN Wiener Neustadt Ost, Austria

Waiting for the plane to feel like it’s the right time to take off can lead to some nasty surprises in some nose heavy types, unless you always have 1000m of runway…

You are taking the weight off the nosewheel, aren’t you? So you can feel when the aircraft is getting light on the mainwheels, yes?

Agreed this is even easier with the little wheel at the back, but any correctly loaded aircraft with the trim set somewhere near correct will tell you when it is ready to fly.

This SC pilot climbs out at 75 mph IAS, which still produces a healthy deck angle. My early SC is flapless so I can’t carry out the hot rod Vx plus full application of flaps departure – hanging on the prop with 45 mph IAS fifty feet AGL suggests a desire for a minor Darwin Award, at the very least.

I didn’t realise there were any flapless Super Cubs. I’d be interested to further my education. The flap jump and hang on the prop is fun for airshows and the like, light on fuel and a bit of headwind will give ground run of the order of twenty metres. It doesn’t take long after take-off to get the speed indicating on the ASI. I agree you don’t want the engine to cough at this point :)

It's supposed to be fun.
LFDW

This stuff has to be type dependent.

For example my TB20 will not lift the nosewheel off by itself, unless trimmed for a speed so low it will probably stall early on in the climb. Well, it might lift it off at something like 90kt, which would translate to a very long runway, and a lot of wear on the mechanicals.

Administrator
Shoreham EGKA, United Kingdom

The original SC was produced for the MDAP between the US and European countries post Korea.

It has a Continental 90 hp engine and while it can be converted to flaps, nearly all were flapless. The flaps became standard with the 135 hp and 150 hp variants. I would need to check, but I think the 105 hp variant (Special) was also mainly flapless.

Oxford (EGTK), United Kingdom

The more I learn about airline pilots (and all that goes in that system) the less inclined I am to step into a tubeliner.

That’s why I always try to take the train when travelling privately

EDDS - Stuttgart

Full flaps on take off can be found in the Morane manuals, too. It depends on the design of plane and procedures.

mh
Aufwind GmbH
EKPB, Germany

I could take off with 36 degs flap in the PA46. I could also take off with the parking brake set. Neither would be a good idea but both would have a similar result….

Last Edited by JasonC at 22 Mar 23:54
EGTK Oxford

Full flaps for takeoff is specified for the Lake Amphibian, which only has “Flaps up” or Flaps down" possible. It depends upon the type. The big flaps of many single Cessnas still enable full flap takeoffs, though they demand skilled flying once airborne.

If an aircraft is trimmed for, or otherwise capable of flying its own nosewheel off during a takeoff roll, it’s going to be a very scary climb! Nosewheels must be lifted to be light/off in the early stages of the takeoff roll, and then held there. As the plane accelerates, and the tail becomes more effective, the back pressure required is reduced so that hopefully, as the plane begins to fly, and then is accelerated to a suitable climb speed, it’s more or less in trim for the climb.

For any tricycle plane, it is required to be capable to lift the nose light in the latter stage of the takeoff roll. Some planes seem more willing than others, but all certified types will do it. The 182 amphib I’m flying recently will do it, but it really want’s you to think it will not. Pilot flies plane, not the other way around.

The pitch attitude achieved when the nose is light on the takeoff roll is exactly the desired attitude when the mains touch at landing. When a pilot masters achieving that nose light pitch attitude, and holding it on takeoff, their landings will greatly improve. And the landing gear will thank them. “Trainers” and aircraft carrier aircraft have forgiving landing gear, most other types like a bit of grace in the flare, and this attitude is how to get there consistently. Taildraggers might be a little different, but not a lot different really….

Home runway, in central Ontario, Canada, Canada

I never suggested WAITING for the nosewheel to become light. I said “taking the weight off the nosewheel” As Pilot DAR is also saying. Of course the pilot flies the plane, but FEEL will tell you when the aircraft wants to fly as long as, as I said “The trim set somewhere near correct”

It's supposed to be fun.
LFDW
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