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Comment by littlestymaar | Hacker News Reader

Tangentially related: you may wonder why they didn't use a pusher propeller[1] in the first place. After all, if the propeller is behind you, then you don't have an issue shooting in front of you, so why didn't they do it? It's because a pusher propeller stabilizes the plane a lot, when you start turning, the propeller applies a force that want to bring it back to its original direction, whereas the puller propeller have the opposite effect, making them much more maneuverable, which is the most important factor in a dogfight.

See this excellent Twitter thread if you want to know more about the mechanical properties of both designs: https://nitter.42l.fr/F22124509/status/1538990570684784645#m

[1]: a pusher propeller is behind the plane, “pushing” it instead of the more common “puller propeller” located in front. For examples of pusher propeller designs, look at popular UCAVs out there, like MQ-9 Reaper and Bayraktar TB2.

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Indeed, some pushers were used early in WW1; e.g. https://en.wikipedia.org/wiki/Royal_Aircraft_Factory_F.E.2

But as you say, the puller turned out to be superior.

Why not both?

https://en.wikipedia.org/wiki/Dornier_Do_335

> making them much more maneuverable, which is the most important factor in a dogfight

as an example problem in statistics class in grad school, we showed that the intuition that maneuverability is most important in a dogfight is incorrect, that it's speed (fly in, take a few shots, zoom away, lather rinse repeat) and that's why WWII fighters were so designed

of course, all else being equal, maneuverability is good, but all else is not equal, there are aerodynamic tradeoffs

Note that WWI and WWII offered a very different fighting environment for pilots, so what's true in one environment doesn't necessarily apply to the other (especially since for WWII fighters, the ability to intercept and shoot down enemy bombers was a very important design consideration).

I'd be curious to learn more about your statistics example though.

it was a problem set type question, with details obscured to avoid our preconceptions, then the true picture revealed afterward; thus, no way of looking up that source. In any event, the data was from WWI and the point was that using their own data they drew the wrong conclusions for their theater based on having plotted it wrong. Had they basically transposed some axes (but counterintuitively to the way they were thinking) the correct trendlines popped right out. We had another similar problem based on the shuttle Challenger o-ring failure/temperature data, given to us as racing car blown engines.

The point of these exercises was to learn to focus on the data statistically/analytically and not by eyeballing presentations, and the obscuring/revealing of the truth was to drive home the point that "lives can depend on this".

The British fighters would sometimes fly in a circle, each pilot watching the tail of the guy in front. Luftwaffe pilot Hans Joachim Marseille figured out a way to beat it.

He'd approach the circle, a bit above it, then dive. He'd pull up towards an airplane on the rim of the circle. Right when his Messerschmitt would stall, he'd be in perfect position to fire into the cockpit of the British pilot, and then fall away. Nobody could follow him.

Doing this successfully required a complete mastery of the airplane. Stall too early, and you won't get a shot in. Stall too late, and you fly right in front of the guns of your opponents. Nobody else was able to make this work, and many died trying.

He racked up 158 kills. He died when his machine suffered engine failure and he bailed out, only to hit the tailplane.

https://en.wikipedia.org/wiki/Hans-Joachim_Marseille

Although a movie was made of his career, The Star of Afrika, it isn't very good.

The Fokker triplane was so agile that it could turn around almost on a dime and face whoever was chasing it.

"Speed is Life."

Spitballing here, but I wonder whether the relatively unsophisticated understanding of aerodynamics meant controlling for clean, laminar air behind the plane was much too difficult?

E: perhaps reading your linked thread before making this comment would’ve been wise of me :)

I'm sure this is mentioned somewhere in that link, but I wonder if it has more to do with that it's easier to build, maintain and fly a front-heavy tractor with short nose, singular tail and shortest driveshaft possible, than about all the airflow considerations.

Thanks, that thread is an excellent discussion of the differences. I had never considered the exhaust contamination of the propeller feed air in a pusher design.

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