couple of questions

[yancovitch]

wonder how a plane shaped like, for example, a killer wale, (with oversized fins), would fly....
also....even in ww-1 there were pushers and tractors...why did the tractors win?...seems to me that pushers might be more efficient.....

[SaultFresh]

Well, with regards to the killer whale question. A lot of it has to do with lift. If those "fins" are designed in the right way, then they can create sufficient lift to get this supposed "killer whale" in the air. As for your question on tractors and pushers. Well, I'm not a history buff or anything, and I certainly wasn't aware of their being pushers in WW1, but all that aside, my thought would be that a pusher would be easier to shoot out of the sky in classic dog-fight style. Where the attacker lines up with the tail of the enemy and takes them down from behind. If the engine is at the rear of the plane, it's probably easier to take it out. Again, no idea if that's the right answer to your question, someone out there probably knows more about it, but that's my educated guess.

[Splinter562]

For pull vs. push:

Pusher configurations are stilled used today, but they typically not a popular choice. Both configurations have their advantages and drawbacks. The tractor configuration tends to be more suitable in general, so unless there is a specific reason to do so, that is usually the configuration that gets used.

Here are a few of the common problems with the pusher configuration that I'm aware of:

• C.G. - Usually, a foward-mounted engine will help offset the weight of the tail structure. With a pusher, you tend to have aft C.G issues.
• Tail Structure - A single-engine pusher prevents you from having a typical tail configuration, so you need to have twin booms to put the tails on.
• Airflow - A tractor prop gets nice clean air to work with. A pusher gets trashier air and is partially obscured by the fuselage.
• FOD (Debris) - Anything that falls off the airplane is going to go through the prop.

As always, Wikipedia has lots to say on the subject:
http://en.wikipedia.org/wiki/Pusher_configuration

[Fozzer]

Of course...

You could have the best of both Worlds... ...

The lovely Cessna 337 Skymaster.... ....!

Push + Pull!

Paul.... 8-)....!

[SaultFresh]

The only problem with the 337 though is that all hell breaks loose if you lose the pusher engine. Also, I don't think the tail-boom design is much of an issue these days. Not when there are a few pushers kicking around that are tail-less.

[olderndirt]

The only problem with the 337 though is that all hell breaks loose if you lose the pusher engine.

Describe this.  As I recall, a multi-engine rating acquired in a 337, restricted you to a 337 because engine out characteristics were so docile.

[SaultFresh]

Well, from my understanding of the 337, which I guess is limited to the fact that I've never flown one, is that the engines are rather weak, even at 210 hp, and that sustaining flight, or climbing to a safe altitude, may be hard, or impossible, on a single engine. It is true though that it garners its own multi-rating, because it's center-line thrust. Aside from that though, the rear engine (again, from my understanding) is susceptible to over-heating and turning off without warning. In any case, I've generally just heard bad things about losing the pusher engine. Then again, I've never flown a 337, and I don't plan on finding out it's single-engine characteristics first hand.

[olderndirt]

Well, from my understanding of the 337, which I guess is limited to the fact that I've never flown one, is that the engines are rather weak, even at 210 hp, and that sustaining flight, or climbing to a safe altitude, may be hard, or impossible, on a single engine. It is true though that it garners its own multi-rating, because it's center-line thrust. Aside from that though, the rear engine (again, from my understanding) is susceptible to over-heating and turning off without warning. In any case, I've generally just heard bad things about losing the pusher engine. Then again, I've never flown a 337, and I don't plan on finding out it's single-engine characteristics first hand.

Most modern light twins have relatively low single engine ceilings.

[Hagar]

Going back to the original question.

also....even in ww-1 there were pushers and tractors...why did the tractors win?...seems to me that pushers might be more efficient.....

I believe the pusher layout was used exclusively by British WWI designers. Not because it was more efficient than tractors. It was just one method tried in the early days of fighter aircraft allowing forward-firing machine guns an unobstructed field of fire. The Airco DH.2 was the first effective single-seater pusher fighter. It was made obsolete with the development of tractor aircraft like the Sopwith Camel & SE.5a fitted with reliable interrupter gear allowing guns to be fired through the prop without hitting it. http://en.wikipedia.org/wiki/Airco_DH.2

A certain Anthony Fokker invented the interrupter gear that gave the German Air Service the edge in 1915. http://en.wikipedia.org/wiki/Fokker_Eindecker

[DaveSims]

The only problem with the 337 though is that all hell breaks loose if you lose the pusher engine.

Describe this.

[olderndirt]

The only problem with the 337 though is that all hell breaks loose if you lose the pusher engine.

Describe this.