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Ask HN: What happened to the Williams Xjet and why no modern equivalent?
Most folks have neither seen or heard of the Williams Aerial Systems Platform (WASP Xjet), a functional VTOL aircraft abandoned by the US military in the 1980s, purportedly due to lack of practical application. Videos of the vehicle in operation are fascinating, arguably exhibiting a concept at least as appealing as the Wingsuit or Gyroplane - both of which have vigorous followings and aren't cheap to own and operate. Perhaps its role in warfare is impractical, but the Xjet would very practically tempt my hypothetical wallet if it were available. Why has such a neat design fallen into obscurity rather than public domain and recreation?
https://en.wikipedia.org/wiki/Williams_X-Jet
- pinewurst 10y agoFor the same reason all of the other 50s, 60s and 70s flying platform/personal VTOL vehicles did. They're expensive, relatively hard to fly, have low endurance/range and not enough payload to be useful. Those F107s are much more cost effective cruising one-way at tree-top with a few hundred pounds (or KT) of boom for their recipient.
- eth0up 10y ago> They're expensive, relatively hard to fly, have low endurance/range and not enough payload to be useful. Both the Wingsuit and gyroplane suffer these attributes too, yet there are many enthusiasts actively engaged in them. Note the potential altitude of the Xjet (1970-80s version) is 10,000' and the operation-time is near 45 minutes - not trivial! The usefulness of the gyroplane isn't terribly extensive, and the Wingsuit less. Affordability seems a valid point of discouragement, but with modern availability of material, manufacturing, etc., maybe not. Sidenote: A former room-mate was building a gyroplane in our living room.
- pinewurst 10y agoI don't believe the 10,000' ceiling number. There's no attribution on the Wikipedia page for it, directly or in references. The duration number is a range but at least the lower 30 min bound seems independently validated by other mentions of the X-Jet's predecessor.
- eth0up 10y agoFirst, a possibly interesting article: https://partners.nytimes.com/library/magazine/home/20000611mag-phenomenon.html https://partners.nytimes.com/library/magazine/home/20000611m... Another article by The Guardian, states that the unabridged explanation for discontinuing the Xjet remains classified; but as you intimate, citations seem on walkabout. I combed some patents for refs on the ceiling-limit and found nothing, to my surprise. I also visited (virtually) both the National Museum of the US Air Force, and Museum of Flight, but curiously couldn't find any results for "X-jet", "Xjet", or "X jet" nor other related keywords. NoScript? Your replies are appreciated, but I remain sincerely perplexed by the persistent obscurity of this fantastic machine. More particularly perplexing is the present year, 2016, where despite solid evidence of a bona fide, functional dream-machine from the 80s offering ballistic capabilities that most humans still futilely fantasize about, we have no tangible modern counterpart to. Even if the X-jet could scarcely tower a hunched inch above the treeline as you mention, it's an inch more free and exhilarating than the best scripted and predictable tangent of any popular rollercoaster. So, respectfully, my question endures. PS: I am no adversary of sausages and am wondering if pinewurst is a genuine product. I immediately think of rosemary, which is a necessary spice in many recipes.
- pinewurst 10y agoI think the answer is that both don't have websites designed for people doing research beyond "what's the cafe menu?" I've been physically to both museums and the USAF museum is truly breathtaking. The Museum of Flight is far less so. I think civilian flying platforms, without some sort of modern fail-safe stability augmentation, would be a regulatory and liability nightmare. Plus the costs would be crazy, if not to buy and operate, to maintain. Zero-timing a jet engine is not a small expense and it's continual. P.S. My nom-de-HN is a tribute to a defunct project's code name. It was a sausage with a thin skin of delusion well stuffed with bad judgment and strongly seasoned with incompetence. Not to my taste at all. P.P.S. There seems to be a lot more info under "WASP" than "X-jet".