Lessons learned from failed prototypes?

[riggerrob]

What lessons have been learned from failed prototypes?

I am thinking in terms of how the AMES AD-1 revealed problems with roll/yaw coupling at steeper angles of wing sweep.

 

[Archibald]

In the french case a) don't eviscerate your entire aircraft industry in 1921: it took until 1952 and two huge failures - 1940 and 1948 - to return it from the grave.

1948 vs 1952 is very interesting...
Cormoran vs Noratlas
Espadon vs Ouragan
SO-4000 vs Vautour
VG-90 vs Sea Venom
PA-28 vs PA-54& PA-55
SO-6000 vs Fouga Magister

I mean, what was overambitious (and murderous) in 1948 became more modest BUT workable in 1952....

 

[sferrin]

What lessons have been learned from failed prototypes?

I am thinking in terms of how the AMES AD-1 revealed problems with roll/yaw coupling at steeper angles of wing sweep.

X-3 did similar. The X-1 showed the need for all-moving tailplanes on supersonic aircraft. Early F-100s exposed roll-reversal. (Don't know if they were the first though.)

 

[Archibald]

Westinghouse J40 expressly showed how NOT to design turbojets.

De Havilland DH-108 showed how not to design tailess supersonic aircraft

Arsenal VG-90 showed how not to design a naval jet combat aircraft.

Comet showed squared windows on pressurised aircraft are not exactly good ideas.

Europa 1 & 2 demonstrated how Ariane shall NOT be build.

Tenerife disaster showed what happen when stupid ATC and fog and too small an airport tries to handle two 747s plus plenty other airliners...

I kind of like @Jemiba signature "Takes a long time, before ALL mistakes are made."

 

[quellish]

Probing the Sky: Selected NACA Research Airplanes and Their Contributions to Flight - NASA

By Curtis Peebles

www.nasa.gov

 

[GK Dundas]

Someone in the early 80s is supposed to have remarked that the DC 10 was the safest airliner currently in service today. If only because they know just about everything that can go wrong with it. This was of course to due to an incredible number of air crashes and other incidents up to that point.

 

[sferrin]

Probing the Sky: Selected NACA Research Airplanes and Their Contributions to Flight - NASA

By Curtis Peebles

www.nasa.gov

I got the impression he was asking for things aircraft discovered that were by accident rather than design.

 

[quellish]

Probing the Sky: Selected NACA Research Airplanes and Their Contributions to Flight - NASA

By Curtis Peebles

www.nasa.gov

I got the impression he was asking for things aircraft discovered that were by accident rather than design.

Why not both?

 

[martinbayer]

Probing the Sky: Selected NACA Research Airplanes and Their Contributions to Flight - NASA

By Curtis Peebles

www.nasa.gov

I got the impression he was asking for things aircraft discovered that were by accident rather than design.

Why not both?

In my view, there is absolutely no reason for not both to be the case.

Personally, I'd be interested in more details of the XFV-12 failure. In my understanding, inadequate comprehension of accurate induced aerodynamic flux conditions due to at the time inadequate computational flow modeling was the main failure mode, but obviously any additional detail would be highly appreciated.

But although this has started as an aircraft thread, I admit that I am sorely itching to add the LM X-33 lifting body LEO VTHL SSTO RLV concept abomination to this tread as an aerospacecraft as well, but moderators, please curate and/or weed my message out as you see fit...

 

[quellish]

Probing the Sky: Selected NACA Research Airplanes and Their Contributions to Flight - NASA

By Curtis Peebles

www.nasa.gov

I got the impression he was asking for things aircraft discovered that were by accident rather than design.

Why not both?

To clarify, I read the book several months ago and there were instances of both accident and by design. There was also a lot of learning what didn’t really work at all as expected

 

[Kat Tsun]

USS Yorktown's computerization experiment showed the US Navy that Windows is bad, so they went with Linux instead for the Zumwalts' IEP installation. Sadly the Royal Navy didn't get that memo. ):

 

[Whisperstream]

What lessons have been learned from failed prototypes?

I am thinking in terms of how the AMES AD-1 revealed problems with roll/yaw coupling at steeper angles of wing sweep.

I wouldn't call the AD-1 a failure in any respect, nor a prototype. It was a pure research aircraft that probably deserved an X-plane designation. Data from the program was useful for evaluating proposals for future oblique-wing aircraft.

The X-3 was, arguably, somewhat of a failure as a research aircraft (again, not a true prototype) due to the fact that it was underpowered, and failed to live up to its potential.

Flight research and testing is often most valuable when it shows what won't work.

 

[riggerrob]

Probing the Sky: Selected NACA Research Airplanes and Their Contributions to Flight - NASA

By Curtis Peebles

www.nasa.gov

I got the impression he was asking for things aircraft discovered that were by accident rather than design.

Why not both?

I am okay with mentioning a few lessons-learned from Mark I, "A" model or 100-series.
Most "A" models have problems, so are only short production runs. It is the "B" or "C" model that gets built in large numbers after most of the bugs were ironed out.
Just look at the Avro Manchester that revealed too many problems with its Rolls-Royce Vulture engines. By the time they reworked the wing to accept 4 Merlin engines, all the major problems were resolved and Lancaster Mark I emerged as a full-fledged heavy bomber.

 

[Nik]

Read some-where that 'R-R Vulture' sorta feasted on its designers' gizzards...
Unclear exactly how many things went terribly wrong...