PA28 All Moving Tail

[spitfire747]

hello all

Just a quick question... does anybody know why piper went for an all moving stabilator on the pa-28 in favour of an elevator type setup

Cheers Spitty

[John Green]

I would think that the reason why the opted for the `all moving horizontal stabaliser` is because it has more authority than the conventional elivator type system, and on a ac of this size it would be more practice than having a elivator on a aerofil. If you look at PA34 TB9/10/20/200/21 there all the same, mainly because the speeds involved arnt that high, therefore at slower speed greater deflection is require and possible with this system. and its probably cheaper to produce also. I hope this helped

[englishal]

Although 152's have an elevator, and are far slower than say a TB20 which can cruise at 150 indicated.Its probably down to design issues. I imagine it is earier to manufactuer a Stabilator....

[Mark 1]

The extra authority would allow a greater CG range - very helpful with 4-seaters.
Jodel changed the arrangement from the Ambassadeur to the Sicile, giving a worthwhile increase in CG envelope, and that fed through to the DR400.

[Miserlou]

And there was some blurb about jet fighters too. The PÅ-28 was born in the days of the early jet fighters which had started to sport this set-up so it was also a statement of state of the art design.

[Tinstaafl]

All of a/c design is a compromise, buffetted by conflicting demands eg efficiency, strength, simplicity, robustness, maintainability & cost. Even marketing & the lawyers gets a look in.

The final design choices are usually after an iterative process that merges on an acceptable compromise that can do the job adequately.

There are advantages and disadvantages to Piper's tailplane solution, just like there are for Cessna's chosen method. Whatever swayed Piper to choose an all-flying tailplane, they obviously thought it had benefits for Piper. Cessna felt otherwise. For Piper the deciding factor could have been something mundane such as perceived marketing ploy or something more technical.

[Flyin'Dutch']

The prize goes to John Green.

Stabilazer allows greater authority over a greater CofG range.

FD

[MLS-12D]

No: John gets the prize, but not because a stabilator is a better concept for slow-moving aircraft ( :hmm::hmm::hmm: ). Rather, as he indicated (and as englishal seconded), it was simpler, and therefore cheaper, for Piper to manufacturer.

It is true that the use of stabilators is common in jet fighters, and so may have influenced Piper's marketing people ... but I doubt that this was a major factor. John Thorp and Fred Weick were the designers, and both men were known for prefering simplicity whenever possible (remember that the PA-28 had 400 fewer parts than the PA-22 that it replaced in Piper's line-up).