Quote:
Originally Posted by Pete Geither
Do front engined planes, and planes with the engines under the wings, and planes with the engines on the tail, all fly different ? Is it like a front wheel drive car versus a rear wheel drive, or even more so ? Just wondering ?
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That all depends on what you mean by “fly differently”.
Once they are in the air and a cruise speed in level flight, they all fly about the same.
Where the engine (thrust) is coming from in relation to the fuselage and control surfaces is more critical when it comes to making changes to said thrust.
The most preferred position is anywhere along the center of the fuselage. The closer to the centerline the better.
The further the thrust is from the centerline. The more leverage it has on the aircraft. Thus – The more attention you need to pay when making changes to it.
The most critical example of this can be found in basic Ultralight aircraft. Many have the center of thrust mounted up above the actual CG and pitch axis (at low speed) of the aircraft. I’ve seen many beginner pilots come in for a landing after slowly decreasing power on approach…they get 10 to 15 feet off the ground and cut the power. The loss of thrust and increase in drag by the prop pitches the nose up. The wing stalls….and they drop. Ouch.
Same with adding power too fast. You’d better be ready to pull the nose up a bit when you nail it.
An example of this in general aviation aircraft are the Lake Amphibians. Awesome aircraft. But, the engine and prop are mounted well overhead in a pod. The saving grace is that they are mounted in line with the tails control surfaces.
DJ has a modified EA300L(p) aerobatic aircraft. Now pushing nearly 400hp (up from stock at 300ish) she can pull the nose straight up and hang the thing at full power on the prop for what seems like forever. Not something you can do if the engine were mounted anywhere else.
There are other issues to take into consideration as well. Such as torque. You don’t feel that come into play so much when the engine is mounted away from centerline. Lots of power/torque mounted dead center can really jack with an aircraft. For example - The P51 is not an aircraft that likes having the throttle shoved forward while starting a takeoff roll. Power Management is a critical lesson in that beast.