47

I like the X-15, it was certainly an amazing airplane, but the truth is there were few benefits to the space program from the X-15. It was far from a critical or necessary step: The Mercury space suit was a direct derivative of the BF Goodrich Navy Mark IV, which had been in use for years. It wasn't developed for the X-15 The rockets used in the space ...


26

I'll complement GdD's answer from a slightly different perspective. In the history of aerospace engineering... Wait, there is a problem right there. Due to various historical reasons, there was no aerospace industry in the USSR, at least the way it is known in the West. The very word "aerospace" was almost never used before the 90s. Aeronautics and ...


10

Great question, but no, the X-15 was not a "critical and necessary step on the path to manned space flight" at all, it was used to test the feasibility of sustained and controlled hypersonic flight of an aircraft at very high altitudes and speeds. The X-15 was an extension of the X program, started in the 1940s, to continuously push the speed envelope of ...


7

The decision was non-technical You can hear it from the test pilots themselves: The rating was actually based on stop lights. Individual requirements (e.g. supercruise) could be rated red, yellow, or green. At the end of the test program, both planes rated green on all requirements. This was all Secretary of the Air Force ...


6

The first issue with airplanes is they are stupendously, freakishly light. Any random American freight diesel locomotive weighs more than a 747-400. Trains rely on this mass to provide the downforce to keep them engaged to the railhead. So your vehicle would need to do something to replace this downforce; for instance have a tubular or I-beam rail which ...


6

The need for throttles is to provide a linkage to the carburetor/throttle body in the age when everything was mechanical. The throttle in older airplanes directly controlled the air-fuel mixture allowed into the intake manifolds. If electric motors were used, the throttles would have been attached to mechanical rheostats. In the age of computer controlled ...


6

Interesting topic. Rockets and spacecraft are still highly experimental vehicles and are recognized as such under 14 CFR §1200. The laws, liabilities, and regulations for private spaceflight are largely uncharted territory at this point, though §1266.102 requires all participants aboard the ISS and NASA launch vehicles to sign a liability waiver prior to ...


4

A lifting tail just means lower static stability. You are correct, flying in the downwash of the wing makes the tail less efficient. But that does not mean it is all bad: Since downwash increases with lift coefficient, the tail effectively sees a smaller angle of attack variation than the wing, so it maintains a healthy margin from stalling even while the ...


3

There were three competing ways to space pursued in the US while in the USSR everything was centrally managed, so they followed only the way that Konstantin Tsiolkovsky had first proposed. What were those three ways? The US Navy used a home-grown team to develop a rocket at the Naval Research Laboratory. Their Vanguard rocket failed several times, however, ...


3

Have a look at the Cri-Cri propeller and jet versions. Yes, jets can be mounted near the nose, but the plane must still balance at within its specified CG range. This is why removing the engine in front and placing jets in back is out (unless you want to really go crazy and mount a Gatling in the front). Remember, it must balance. However, at Cessna (152) ...


3

It's called the Ampaire Tailwind, and as this article explains, it only exists in scale models and renderings at the moment.


3

From Mason’s Perspective on the X-29: The other issue with this airfoil is that every Grumman aerodynamicist felt the need to “improve” it, so that there were many variations. I think the airfoil that was used on the X-29 was known as K-Mod 2. I’m not sure anybody can say with certainty what the actual airfoil coordinates are. Grumman was not good with ...


2

Ground effect is measured using the non-dimensional height parameter 'h/c', i.e. the height above ground divided by the chord length. By increasing the chord length, the height of the maximum efficiency height is raised, as the location of the h/c does not change. Increasing the span also adds efficient lift due to aspect ratio effects, however creating too ...


2

You asked for it, you got it: The x number of small non-certified engines will not add redundancy, they are in fact very noisy, and terribly uneconomical (as a reply to your comment). The good old piston engine is extremely reliable compared to these mini jets. Certified GA pisyon engines are tried and tested, and you can bet your mamas behind that they ...


2

what about just 1 throttle, and 2 or 3 backup throttles for redundancy as they are electronic and could easily be blown You wouldn't need separate levers for that: just have one lever driving two or more throttle position sensors. You might want separate levers for the left-side and right-side engines, so you can use differential throttle control to steer ...


1

It is not actually true that ... the tailplane configuration ... requires the main wing to provide higher lift than the weight of the plane itself What matters for stability is that the change in lift moment of the tail should be greater than that of the main wing; the absolute value of its lift is not relevant. The lifting tail has been well ...


1

Focusing on the aircraft in the picture, lifting tail aircraft are essentially bi-planes. The single lifting wing has proved to be more efficient long ago. Simple adjustment of the CG removes the need for a lifting tail. This plane could be flown that way. It is the job of the tail to set the wing at a given AOA, using aerodynamic force in flight to hold ...


Only top voted, non community-wiki answers of a minimum length are eligible