Sometimes you see a vintage plane that makes you scratch your head. Case in point is the US Air Force’s X-29 of the 1980s that looks like a fighter with the wings stuck on backwards. Was this a daft mistake or a great leap forward? Let’s have a look.
If you visit the National Museum of the Air Force in Dayton, Ohio or NASA’s Armstrong Flight Research Center in Edwards, California, you’re likely to see one to two prototypes of one of the oddest aircraft to leave the drawing board.
The Grumman X-29 may resemble the product of some kid who put together a model airplane without reading the instructions, but there was some serious thinking behind building an aircraft with its wings sweeping dramatically forward instead of back.
In the 1930s, aeronautical engineers were fooling about with all manner of wings. When you don’t fully understand things like that, you have an excuse. There were box wings, tube wings, cantilever wings, rotating wings, and wings that looked like Venetian blinds. If you could imagine a wing, someone was building it.
One idea was to sweep the wings forward instead of back. The idea was that such a wing would reverse the usual flow over it. Where a conventional back-swept wing has the air flowing from the root to the tips, a forward swept one flows from the tip to the roots. This results in reduced drag, greater maneuverability, and the ability to fly at a steeper angle of attack.
The concept was put into practice by Germany during the Second World War with the Junkers Ju 287 jet tactical bomber. It was later incorporated into the civilian Hansa Jet HFB-320 in the 1960s, but in both cases the wings were far from a success because of the tendency of the wings to be unstable due to excessive wing flexing.
In the 1970s, DARPA, the US Air Force, and NASA decided to take another look at the concept thanks to the development of new carbon composites that promised to make forward-swept wings more rigid without adding too much weight, as well as advances in computing technology that now had a chance of controlling an inherently unstable airframe that could get out of shape faster than a human pilot could be expected to correct for it.
The result was the X-29, which first took flight in 1984 and acted as a research testbed until 1992.
Two of the prototypes were built and from the outset they had a strange yet familiar profile. The odd wings were set far back on the fuselage, and instead of having tail stabilizers they had canards set forward of the wings. The familiarity sprang from the fact that the designers saved money by basing the design on an F-5 Freedom Fighter fuselage with the undercarriage from an F-15.
The X-29 had some very decent performance cred. Its General Electric F404-GE-400 engine produced a maximum of 16,000 pounds of thrust, giving it a top speed of Mach 1.5, an operational ceiling of 50,000 ft (15,000 m) and an endurance around one hour of flying time.
NASA
However, as expected, it was as unstable as all get-out.
This isn’t always a bad thing; one pilot’s instability is often another’s idea of extreme agility, and in the era of the dogfight, the ability to turn on a dime was such an enormous advantage that some of the best aircraft were notoriously touchy at the stick. The Sopwith Camel, for example, took more enemy scalps than any other allied aircraft in WW1, thanks largely to its extreme handling capabilities.
But this instability made it notoriously difficult to fly – and indeed, nearly as many Camel pilots died during training as were lost in combat. The torque reaction from its large rotary engine made it so much faster turning right than left that some pilots preferred doing a Zoolander-style spin to a direct left turn. A stall would immediately result in a deadly tailspin. And a full tank of fuel moved the center of gravity back beyond the safe limit, resulting in a lot of crashes on takeoff.
Likewise, Germany’s Fokker D7 was also highly touchy at the controls, particularly in prototype form; its thicker-than-usual wings resulted in some sketchy directional instability in a dive. When the Fokker company tried to sell the D7 to the German Luftwaffe during the First World War, they reportedly did their best to sell this as a feature, telling the German test pilots that the D7 was “ultra maneuverable.”
Grumman’s answer for the X-29’s antisocial degree of aerodynamic instability was to install a state-of-the-art fly-by-wire system that corrected the craft’s flight 40 times per second. Corrections were made by three computers on the basis of two computers outvoting the third.
And watching the thing in flight, the X29 certainly seems to have an extraordinary capability for lightning-fast turns and rolls – but it certainly needed that digital assistance. “If the aircraft didn’t have that flight control system…” test pilot Rogers E. Smith tells Fighter Pilot Podcast in the video below, “that airplane at 250 knots would likely break in half. Because it’s 0.12 seconds to double amplitude. It’d double its amplitude, that’s how divergent it was, every 0.12 seconds.”
In many ways the X-29 was a great success, providing US engineers with stacks of data that would be used in later aircraft designs. However, the wing’s performance was not as great an advancement as had been hoped for.
In the end, the decision was made to base future fighter and bomber designs on new stealth technology, picking relative invisibility over hyper-maneuverability.
Still, it sure did spice up some toy plane and bedroom poster lineups in the 1980s!
Source: NASA
ADVERTISEMENT:
Informasi mengenai KING SLOT, Segera Daftar Bersama king selot terbaik dan terpercaya no satu di Indonesia. Boleh mendaftar melalui sini king slot serta memberikan hasil kembali yang paling tinggi saat sekarang ini hanyalah KING SLOT paling gacor, gilak dan gaco saat sekarang di Indonesia melalui program return tinggi di kingselot serta pg king slot
suara88 permainan paling top dan garansi imbal balik hasil besar bersama https://suara88.biz/
sumo7777 permainan paling top dan garansi imbal balik hasil besar bersama https://sumo7777.com/
supermoney888 permainan paling top dan garansi imbal balik hasil besar bersama https://supermoney888.biz/
teratai88 permainan paling top dan garansi imbal balik hasil besar bersama https://teratai88.biz/
thor88 permainan paling top dan garansi imbal balik hasil besar bersama https://thor88.biz/
togelhk88 permainan paling top dan garansi imbal balik hasil besar bersama https://togelhk88.net/
topjitu88 permainan paling top dan garansi imbal balik hasil besar bersama https://topjitu88.net/
totosloto88 permainan paling top dan garansi imbal balik hasil besar bersama https://totosloto88.com/
trisula888 permainan paling top dan garansi imbal balik hasil besar bersama https://trisula888.biz/
udangbet88 permainan paling top dan garansi imbal balik hasil besar bersama https://udangbet88.net/
via88 permainan paling top dan garansi imbal balik hasil besar bersama https://via88.biz/
virusjp88 permainan paling top dan garansi imbal balik hasil besar bersama https://virusjp88.net/
warga888 permainan paling top dan garansi imbal balik hasil besar bersama https://warga888.biz/
waw88 permainan paling top dan garansi imbal balik hasil besar bersama https://waw88.biz/
winjitu88 permainan paling top dan garansi imbal balik hasil besar bersama https://winjitu88.net/
wisdom88 permainan paling top dan garansi imbal balik hasil besar bersama https://wisdom88.biz/
wnitogel88 permainan paling top dan garansi imbal balik hasil besar bersama https://wnitogel88.com/
yoyo888 permainan paling top dan garansi imbal balik hasil besar bersama https://yoyo888.biz/
validtoto88 permainan paling top dan garansi imbal balik hasil besar bersama https://validtoto88.com/
sule999 permainan paling top dan garansi imbal balik hasil besar bersama https://sule999.com/
sule88 permainan paling top dan garansi imbal balik hasil besar bersama https://sule88.org/
ss888bet permainan paling top dan garansi imbal balik hasil besar bersama https://ss888bet.com/
sia77 permainan paling top dan garansi imbal balik hasil besar bersama https://sia77.info/
seluang88 permainan paling top dan garansi imbal balik hasil besar bersama https://seluang88.com/
satu88 permainan paling top dan garansi imbal balik hasil besar bersama https://satu88.biz/
satu777 permainan paling top dan garansi imbal balik hasil besar bersama https://satu777.asia/
rp88 permainan paling top dan garansi imbal balik hasil besar bersama https://rp88.biz/
rp88 permainan paling top dan garansi imbal balik hasil besar bersama https://rp88.asia/
rp88 permainan paling top dan garansi imbal balik hasil besar bersama https://rp77.live/
qiuqiu88 permainan paling top dan garansi imbal balik hasil besar bersama https://qiuqiu88.biz/
pt88 permainan paling top dan garansi imbal balik hasil besar bersama https://pt88.org/
pt77 permainan paling top dan garansi imbal balik hasil besar bersama https://pt77.info/
produk88 permainan paling top dan garansi imbal balik hasil besar bersama https://produk88.asia/
mt88 permainan paling top dan garansi imbal balik hasil besar bersama https://mt88.org/
mt77 permainan paling top dan garansi imbal balik hasil besar bersama https://mt77.biz/
menang66 permainan paling top dan garansi imbal balik hasil besar bersama https://menang66.biz/
latobet888 permainan paling top dan garansi imbal balik hasil besar bersama https://latobet888.org/
kedai96 permainan paling top dan garansi imbal balik hasil besar bersama https://kedai96.org/
kedai188 permainan paling top dan garansi imbal balik hasil besar bersama https://kedai188.biz/
ids88 permainan paling top dan garansi imbal balik hasil besar bersama https://ids88.biz/
hp88 permainan paling top dan garansi imbal balik hasil besar bersama https://hp88.org/
hp77 permainan paling top dan garansi imbal balik hasil besar bersama https://hp77.org/
gm88 permainan paling top dan garansi imbal balik hasil besar bersama https://gm88.asia/
gm77 permainan paling top dan garansi imbal balik hasil besar bersama https://gm77.net/
final888 permainan paling top dan garansi imbal balik hasil besar bersama https://final888.org/
duit88 permainan paling top dan garansi imbal balik hasil besar bersama https://duit88.asia/
duit168 permainan paling top dan garansi imbal balik hasil besar bersama https://duit168.biz/
divisi88 permainan paling top dan garansi imbal balik hasil besar bersama https://divisi88.org/
dewi500 permainan paling top dan garansi imbal balik hasil besar bersama https://dewi500.biz/
devil88 permainan paling top dan garansi imbal balik hasil besar bersama https://devil88.info/
cuputoto88 permainan paling top dan garansi imbal balik hasil besar bersama https://cuputoto88.com/
cukongbet88 permainan paling top dan garansi imbal balik hasil besar bersama https://cukongbet88.asia/
bom888 permainan paling top dan garansi imbal balik hasil besar bersama https://bom888.biz/
bintaro888 permainan paling top dan garansi imbal balik hasil besar bersama https://bintaro888.info/
askasino88 permainan paling top dan garansi imbal balik hasil besar bersama https://askasino88.org/
999aset permainan paling top dan garansi imbal balik hasil besar bersama https://999aset.com/
afb77 permainan paling top dan garansi imbal balik hasil besar bersama https://afb77.biz/
aset99 permainan paling top dan garansi imbal balik hasil besar bersama https://aset99.biz/
bendera77 permainan paling top dan garansi imbal balik hasil besar bersama https://bendera77.biz/
bendera888 permainan paling top dan garansi imbal balik hasil besar bersama https://bendera888.com/
coco88 permainan paling top dan garansi imbal balik hasil besar bersama https://coco88.org/
cuma77 permainan paling top dan garansi imbal balik hasil besar bersama https://cuma77.biz/
cuma88 permainan paling top dan garansi imbal balik hasil besar bersama https://cuma88.org/
dwv88 permainan paling top dan garansi imbal balik hasil besar bersama https://dwv88.org/
fafajp88 permainan paling top dan garansi imbal balik hasil besar bersama https://fafajp88.com/
gemar88 permainan paling top dan garansi imbal balik hasil besar bersama https://gemar88.biz/
gocap88 permainan paling top dan garansi imbal balik hasil besar bersama https://gocap88.info/
gocaptoto permainan paling top dan garansi imbal balik hasil besar bersama https://gocaptoto.asia/
hakabet88 permainan paling top dan garansi imbal balik hasil besar bersama https://hakabet88.com/
hwtoto88 permainan paling top dan garansi imbal balik hasil besar bersama https://hwtoto88.org/
ina77 permainan paling top dan garansi imbal balik hasil besar bersama https://ina77.biz/
ina88 permainan paling top dan garansi imbal balik hasil besar bersama https://ina88.info/
jingga8888 permainan paling top dan garansi imbal balik hasil besar bersama https://jingga8888.com/
juragan777 permainan paling top dan garansi imbal balik hasil besar bersama https://juragan777.asia/
kastil77 permainan paling top dan garansi imbal balik hasil besar bersama https://kastil77.info/
kebo888 permainan paling top dan garansi imbal balik hasil besar bersama https://kebo888.biz/
kkwin77 permainan paling top dan garansi imbal balik hasil besar bersama https://kkwin77.com/
kokoslot88 permainan paling top dan garansi imbal balik hasil besar bersama https://kokoslot88.asia/
luckydf88 permainan paling top dan garansi imbal balik hasil besar bersama https://luckydf88.org/
microstar888 permainan paling top dan garansi imbal balik hasil besar bersama https://microstar888.biz/
monperatoto88 permainan paling top dan garansi imbal balik hasil besar bersama https://monperatoto88.com/
mpo1122 permainan paling top dan garansi imbal balik hasil besar bersama https://mpo1122.biz/
mpo122 permainan paling top dan garansi imbal balik hasil besar bersama https://mpo122.biz/
mpopelangi88 permainan paling top dan garansi imbal balik hasil besar bersama https://mpopelangi88.com/
pamanslot88 permainan paling top dan garansi imbal balik hasil besar bersama https://pamanslot88.biz/
panel88 permainan paling top dan garansi imbal balik hasil besar bersama https://panel88.org/
paragon77 permainan paling top dan garansi imbal balik hasil besar bersama https://paragon77.biz/
paragon888 permainan paling top dan garansi imbal balik hasil besar bersama https://paragon888.info/
pion77 permainan paling top dan garansi imbal balik hasil besar bersama https://pion77.biz/
prada88 permainan paling top dan garansi imbal balik hasil besar bersama https://prada88.asia/
prada888 permainan paling top dan garansi imbal balik hasil besar bersama https://prada888.com/
qqslot88slot permainan paling top dan garansi imbal balik hasil besar bersama https://qqslot88slot.com/
rejekibet88 permainan paling top dan garansi imbal balik hasil besar bersama https://rejekibet88.com/
rezekibet88 permainan paling top dan garansi imbal balik hasil besar bersama https://rezekibet88.org/
sensa77 permainan paling top dan garansi imbal balik hasil besar bersama https://sensa77.biz/
sensa888 permainan paling top dan garansi imbal balik hasil besar bersama https://sensa888.biz/
singajp88 permainan paling top dan garansi imbal balik hasil besar bersama https://singajp88.com/
sr77 permainan paling top dan garansi imbal balik hasil besar bersama https://sr77.org/
sr88 permainan paling top dan garansi imbal balik hasil besar bersama https://sr88.org/
surya77 permainan paling top dan garansi imbal balik hasil besar bersama https://surya77.biz/
surya88 permainan paling top dan garansi imbal balik hasil besar bersama https://surya88.asia/
tajir77 permainan paling top dan garansi imbal balik hasil besar bersama https://tajir77.info/
tajir88 permainan paling top dan garansi imbal balik hasil besar bersama https://tajir88.biz/
toto122 permainan paling top dan garansi imbal balik hasil besar bersama https://toto122.com/
toto123 permainan paling top dan garansi imbal balik hasil besar bersama https://toto123.biz/
uangvip88 permainan paling top dan garansi imbal balik hasil besar bersama https://uangvip88.com/
wajik77 permainan paling top dan garansi imbal balik hasil besar bersama https://wajik77.asia/
777neko permainan paling top dan garansi imbal balik hasil besar bersama https://777neko.org/
88judi permainan paling top dan garansi imbal balik hasil besar bersama https://88judi.net/
99judi permainan paling top dan garansi imbal balik hasil besar bersama https://99judi.org/
abcslot88 permainan paling top dan garansi imbal balik hasil besar bersama https://abcslot88.asia/
slot demo gacor permainan paling top dan garansi imbal balik hasil besar bersama https://kdwapp.com/
akun demo slot gacor permainan paling top dan garansi imbal balik hasil besar bersama https://kdwapp.com/
akun slot demo gacor permainan paling top dan garansi imbal balik hasil besar bersama https://kdwapp.com/
akun demo slot pragmatic permainan paling top dan garansi imbal balik hasil besar bersama https://kdwapp.com/
akun slot demo pragmatic permainan paling top dan garansi imbal balik hasil besar bersama https://kdwapp.com/
akun slot demo permainan paling top dan garansi imbal balik hasil besar bersama https://kdwapp.com/
akun demo slot permainan paling top dan garansi imbal balik hasil besar bersama https://kdwapp.com/
slot demo gacor
akun demo slot gacor
akun slot demo gacor
akun demo slot pragmatic
akun slot demo pragmatic
akun slot demo
akun demo slot
slot demo gacor permainan paling top dan garansi imbal balik hasil besar bersama https://jebswagstore.com
akun demo slot gacor permainan paling top dan garansi imbal balik hasil besar bersama https://jebswagstore.com
akun slot demo gacor permainan paling top dan garansi imbal balik hasil besar bersama https://jebswagstore.com
akun demo slot pragmatic permainan paling top dan garansi imbal balik hasil besar bersama https://jebswagstore.com
akun slot demo pragmatic permainan paling top dan garansi imbal balik hasil besar bersama https://jebswagstore.com
akun slot demo permainan paling top dan garansi imbal balik hasil besar bersama https://jebswagstore.com
akun demo slot permainan paling top dan garansi imbal balik hasil besar bersama https://jebswagstore.com
slot demo gacor
akun demo slot gacor
akun slot demo gacor
akun demo slot pragmatic
akun slot demo pragmatic
akun slot demo
akun demo slot
slot demo gacor permainan paling top dan garansi imbal balik hasil besar bersama https://demoslotgacor.pro
akun demo slot gacor permainan paling top dan garansi imbal balik hasil besar bersama https://demoslotgacor.pro
akun slot demo gacor permainan paling top dan garansi imbal balik hasil besar bersama https://demoslotgacor.pro
akun demo slot pragmatic permainan paling top dan garansi imbal balik hasil besar bersama https://demoslotgacor.pro
akun slot demo pragmatic permainan paling top dan garansi imbal balik hasil besar bersama https://demoslotgacor.pro
akun slot demo permainan paling top dan garansi imbal balik hasil besar bersama https://demoslotgacor.pro
akun demo slot permainan paling top dan garansi imbal balik hasil besar bersama https://demoslotgacor.pro
slot demo gacor
akun demo slot gacor
akun slot demo gacor
akun demo slot pragmatic
akun slot demo pragmatic
akun slot demo
akun demo slot
slot demo gacor permainan paling top dan garansi imbal balik hasil besar bersama https://situsslotterbaru.net
akun demo slot gacor permainan paling top dan garansi imbal balik hasil besar bersama https://situsslotterbaru.net
akun slot demo gacor permainan paling top dan garansi imbal balik hasil besar bersama https://situsslotterbaru.net
akun demo slot pragmatic permainan paling top dan garansi imbal balik hasil besar bersama https://situsslotterbaru.net
akun slot demo pragmatic permainan paling top dan garansi imbal balik hasil besar bersama https://situsslotterbaru.net
akun slot demo permainan paling top dan garansi imbal balik hasil besar bersama https://situsslotterbaru.net
akun demo slot permainan paling top dan garansi imbal balik hasil besar bersama https://situsslotterbaru.net
slot demo gacor
akun demo slot gacor
akun slot demo gacor
akun demo slot pragmatic
akun slot demo pragmatic
akun slot demo
akun demo slot
situs slot terbaru
slot terbaru