Talk:Dutch roll

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This technique is more commonly referred to as a slip. If the airspeed is allowed to decay the aircraft can stall, and the crossed controls can cause it to spin

That's completely untrue. Stalling in a side slip will NOT induce a spin.

Also, the speed is irrelevant in stalling a side slip. If you pull the stick back to the point of stall with crossed controls, you will fall out of the sky like a brick and may even notice an increase in airspeed.

>>>>>>>>>> I beg to differ. I don't know where you got your information, but I spent three years in an aero engineering program, I've been a private pilot for more than 10 years, and I'm building an Experimental aircraft.

Stalling with crossed controls is *precisely* how you enter a spin. Not all aircraft WILL spin, but the sentence is accurate as it stands - a spin CAN result from a stall with crossed controls.

A sideslip will normally result in an increase in descent rate without an increase in airspeed. Pilots of aircraft without flaps (such as the one I'm building) commony use sideslip to control rate of decent on final approach. For a wheels-eye view of what that looks like, see this video clip: Video of a slip from camera mounted on landing gear

Brendano 13:40, 29 August 2005 (UTC)

______________ That's fine - You can beg to differ if you want. I got my "information" from years of competing in aerobatics. Thanks for the video - I fly a Pitts - I see that every time I land.

First you say that crossed controls is "precisely" how you enter a spin - And then the very next sentence you say that this will not put all aircraft into a spin.. So which is it? If you think crossed controls is "precisely" how you get into a spin, we'd better let CIVA, Haute Voltige and all aerobatic training organisations know that they've been doing "precisely" the wrong thing all these years - That is stick full back an full rudder... Thanks for clarifying this for us.

I suspect you were thinking of accelerated spins - where the controls are crossed - But this is done AFTER the spin has been initiated. If you pull full backstick with crossed controls (accelerated stall in a sideslip) - it won't enter a spin. I tried this several times out of curiosity before I posted. See this video of an accelerated spin: http://www.airborne-aviation.com.au/gallery/videos/pitts050813-spins.wmv The controls aren't crossed until one full rotation has been avhieved - For this reason.

Also - Being a Pitts pilot I obviously know that a controlled sideslip on finals will increase descent rate without increasing airspeed - Read what I wrote again - if you induce and sustain a stall in a sideslip, airspeed MAY (and most likely will) increase as you plunge to Earth.

It's one of those aviation myths - Like falling out of downwind turns and bernoulli being the primary generator of lift... I know we'll just have to agree to disagree on this.

[edit] Technical

I added the "too technical" comment here and at phugoid because I had no idea what a "rudder singlet or doublet" is. Most of the article is a little beyond the average reader, I think, but it's a fairly esoteric topic. Still, it could be made more accessible.--andersonpd 22:58, 26 October 2005 (UTC)

I added a common language first sentence and some clarifying details on singlets & doublets. I'm removing the technical tag. Knotnic 22:26, 21 December 2005 (UTC)

Believe me, this is as non-technical a description as is possible. I would have started with the factorisation of the lateral stability quartic. You know, kept things nice and simple by just considering stick-fixed stability. Gordon Vigurs 08:13, 30 May 2006 (UTC)

[edit] Aerobatics doesn't seem to pay off

Sorry to tell you Brendano but you are incorrect. I have been a flight instructor for some time and have flown many different airplanes. If you recall from AC 61-67 a spin is "an aggravated stall resulting in autorotation." You are correct that a stall while in a sideslip will greatly increase rate of descent. Also, in MOST airplanes a slip will not result in a spin if actions are taken within a reasonable amount of time to counteract the situation. The determining factor is the stability characteristics, control authority, and weight and balance. I have put airplanes into a spin both through slips, and skids. It sounds like you are speaking from experience in a Pitts which I have not had the pleasure to fly, but your dear friend above has hands down won the argument.