In November 1941 the USAAF ordered two prototype XB-35 flying wing bombers, powered by four 2237kW Pratt & Whitney R-4360 Wasp Major piston engines driving eight-bladed counter-rotating pusher propellers. A further 13 aircraft, designated YB-35, were ordered in early 1943. There were many problems with the propellers and gearboxes, but the first XB-35 made its maiden flight on 25 June 1946, followed by the second in the following year.
|A three-view drawing (700 x 458)|
| ENGINE||4 x Pratt & Whitney R-4360 Wasp Major, 2237kW|
| Take-off weight||76340 kg||168302 lb|
| Wingspan||52.4 m||172 ft 11 in|
| Length||16.2 m||53 ft 2 in|
| Wing area||372 m2||4004.17 sq ft|
| Max. speed||605 km/h||376 mph|
| Range||10000 km||6214 miles|
|Terrence O'Neill, e-mail, 19.12.2011 18:36|
The top pic is gthe YB-35; the bottom is the XB-35. Performance depends on wing loading, power loading, wetted area per HP, and fineness ratio. The B-35 was far superior to the B-36 in every instance. These are 'configuration parameters' and as both planes used the same engine, nothing -- nothing - could be done to improve the B-36 that couldn't be done to the B-35. The AF Generals tried, but they just didn't understand aerodynamics. See my eBook "Goodbye Beautiful Wing" on Amazon.
|kestrel341, e-mail, 17.09.2011 05:13|
This is the same as the B-58s being used as negotiating chips. Anything unconventional is initially going to be expensive and have teething problems (although I don't know if the V-22s were worth it). Look at the last two major fighter competitions. Northrop had the edge in the Black Widow 2, look how the Chinese have copied it. With split chin intakes, the Boeing X-32 would have beat out Lockheed too, especially the delta winged version. It must have been politics right down the line (after all, who was President? Where is Lockheed /GD?) OK. Well, that explains it. It's like the P-38 limited to Allisons rather than Merlins because something had to use all those Allisons...when they put a Merlin in the P-51, it outclassed everything.
|Panintheas, e-mail, 19.08.2011 11:51|
Symington offered Northrup a deal for a new startup company. Symington and friends would have been major stockholders, they were to "grease the skids and open a new era in aircraft. When Northrup refused,Symington became a personal enemy to Northrup. Contracts were torn up planes destroyed, and a new more efficient class of air frame was quashed for years.
|HEXJUMPER, e-mail, 28.07.2011 18:55|
how come only Northrop's aircraft were destroyed on purpose for not having paid USAF PARCING FEES ? i have never ever read such reason anymore for many other aircraft from different aircraftbuilders.bizar enough none of the famous big wing aircraft have been preserved also.
|Terrence O'Neill, e-mail, 08.12.2010 18:52|
Note to firstname.lastname@example.org, re your 07.03.2010: Check out Gary Pape's excellent book on Northrop Wings... specs same as in my copy of Northrop's XB-35 Erection and Maintenance Manual, that the Wing airfoil was a 65-019 in the center and -018 at the tips, with a 26d sweep;and the B-36's was a thicker 64- series airfoill with only 18d sweep...resulting Mcrit was over.75 for the Northrop, and under .70 for the B-36. The Wing airframe was flown to 520 mph at over 40,000 ft.... and the B-36's wing was limited by flutter to a much lower speed... something that required redesign of the wing to a different even slower airfoil during construction of the prototypes.
The bomb load required was only 10,000 lbs., and the Convair brag of 80,000 or so lbs is irrelevant because all that capacity was all required by the B-36 to be used as fuel to fly the required range with one Mk.3 FatMan. I have less credibility for Edwards' comments, as he pulled the wings off the YB-49 #2 by starting the stall tests too low to permit gradual recovery. The AF test pilots then refused to fly the stall tests, so Northrop's Chuck Tucker -- who I interviewed in 2003-- told me he started them at 30k (instead of est. 15k by Edwards) and had a G-meter put on the instrument panel so he wouldn't exceed 3Gs. Check flew all the stall tests and autopilot installation flights, in the Wing more than 100 hours. On the last stall, started recovery too soon and spun (and recovered) it, and had photos to prove it. He was in it when they found GCI radar couldn't see it on several passes... i.e. it was STEALTHY in 1948. The AF Generals -- who learned to fly in biplanes-- ignored this. The Wings were sabotaged and trashed because Jack Northrop refused to merge his profitable company with the bankrupt Convair owned by Floyd Odlum, whose former Convair-Director Louis Johnson had become the US Secretary of Defense, and persuaded AF Sec Symington to cancel Wing contracts, a Navy carrier, and a hundred AF production contracts in order to buy more B-36s to save Convair... which resulted in a Congressional Investigation... and a whitewash job...per persuasive circumstantial evidence. Within a year the Russians exploded their first nuke. Then as soon as the Stealthy Wings were trashed by Symington the N. Koreans started the Korean War. A perfect opportunity for the B-36 to use its great bomb load capacity... never used. Congress and the Generals in their wisdom bought billions worth of worthless B-36s, and retired the remaining ones as soon as the crew-killing B-47s (with only 1500 miles radius) finally got the bugs out in the mid-50s. And on and on.... it's all in my revised book Goodbye Beautiful Wing, available from Amazon probably in a few weeks.
|Terrence O'Neill, e-mail, 03.11.2010 18:08|
email@example.com, you must have read my book *GM,DS! A Billion Dollar Blunder).
If not, wait for the revision hopefully done this year, to be re-titled "Goodbye Beautiful Wing", with irrelevant stuff excised, and some additional mind-boggling facts added that were not included in GM,DS!
|coleighf, e-mail, 07.03.2010 21:20|
There's a lot of wishful thinking about all of the flying wing projects, which is understandable, but whether Horten, Northrop or Armstrong Whitworth, they had all fundamental flaws related to straight line accuracy which would have affected bomb-aiming capability, or in the case of Horten, suitability as a gun platform.
Additionally with the B35 and B49 the thickness /chord ratio of 23% at the centre section must have given a very low limiting mach number, the 49 was probably close to the limit of compressibility at maximum speed above 30,000feet and almost certainly would have been into it with any acceleration in a shallow dive.
The reports written by Glen Edwards certainly describe a machine which could get very frightening very quickly, and I'd be surprised if loss of control through inadvertent exceedance of a very low limiting mach number was not the cause of the airframe break up and the death of him and all of his crew. I know that theorising about political conspiracies is a great thing to do when we see the failure of something we would all love to succeed, but I don't doubt that cancelling of the program was the sensible decision before a load more money got wasted and more skilled aircrew died for no excusable reason.
I find it hard to see how the B47 could be described as a failure compared to the B49 and really the range of the B49 combined with bomb load did not really make it directly comparable with the B36, which with all of it's limitations did a stalwart job for SAC for a number of years before the magnificent B52 got into service.
|stanley sandler, e-mail, 03.02.2009 18:05|
Sooo, what y'all are saying is that the Secretary of the Air Force really didn't give a tinker's damn about the safety of the United States, just for his "drinking buddy" Harry Truman (who I guess also didn't give a damn, although he publicly said that the country "should build more of them."), and his partner in financial crime, Symington. That's a stretch. Why not check with the Office of AF History --(or are they in on the racket too?)
Stanley Sander, Ph.D.
|Joseph, e-mail, 26.12.2008 20:46|
The government did what is has always done and will always do.
Line their own pockets first and take care of their richest supporters. Those who dissent are ultimately hounded and destroyed, unless there is a big enough public outcry of the government's treachery, greed, and stupidity. While the greatest amount of freedom is enjoyed here, it comes at a high price.
|Terrence O'Neill, e-mail, 22.05.2008 17:12|
Moreover, the B-35 was a 4000-mile-target bomber with more range than the Convair B-36, a fact that was concealed by the AF writing-down its gross-weight by claiming no landing gear test! Jack Northrop said the airframe was designed for 300,000-lbs., but the AF refused to load test it. That the instability claims were bogus is given lie by statements by Charles Tucker, Northrop test pilot who flew the YB-49 (a YB-35 airframe with only powerplane changes) through all the AF stall tests AFTER the No. 2 YB-49 crashed when pilot Forbes pulled the wings off at 4.8Gs, after starting the stall too low for a gradual recovery. The engine and gear-box problems were the result of the AF failing to perform engine-prop compatibility tests before sending THEIR engines to Northrop to use... and the AF repeatedly refusing to do the standard compatibility tests to correct the resonance. United Aircraft owned both P&W and Hamilton Standard, both located in the same town in Connecticut. AAF top General Hap Arnold actually ordered production of 200 B-35 Wings in 1942,and did not order any Consolidated-Vultee (Convair) B-36s until ordered to do so by the Secretary of War. And the production order was cancelled two years later as the result of a mysterious 'latest information' note that made false claims about a reduction in Northrop's design performance, claims proven by NACA to be false later that year ... but too late, the production contracts haveing been cancelled in wartime.
With a simple fix to the gearbox (later claimed to have beeen accomplished by P&W), the B-35 would have been able to overfly all 19,000 USSR interceptors, and could have been modified into an ultra-long-range gunship able to outperform the higher-wing-loading Mig-15s at 45,000-ft. But first AF Secretary Stuart Symington instead chose to save his friend Floyd Odlum's Convair Corporation from bankruptcy in 1949, indicated by Convair's Annual Reports. And, of course, all the mods done to the B-36 to 'improve it' could have also have been done to the B-35, to keep it flying to targets a thousand miles more distant, 75 mph faster and two miles higher. Simply because the configuration of the Wing gave it a lower wing loading, a higher power loading, and a higher power-to-wetted-area loading. The B-36 was designed to be inferior from the start, and nothing could have saved it.
|Iron Mountain Man, e-mail, 21.01.2008 23:53|
This aircraft was built to the same specification as the Consolidated-Vultee /Convair /General Dynamics B-36 to bomb Europe from North American bases.
(5,000 statute mile action radius with 10,000 lbs. bombs at 35,000 feet AGL and able to fight off hostile interceptors)
The XB-35 accomplished this easily and used a LOT less fuel and hardware to accomplish this mission profile than the 10 engined B-36. The 'Wing also was a lot more reliable and safer than the -36 without the structural problems and fuel and oil leaks and engine fires that constantly plagued the Fort Worth Monster. The 'Wing could also out manouver any fighter above 40,000 feet AGL and out run them as well and was nowhere near as fatiguing to fly as the -36.
Plus it was near invisible to ground control intercept radar. Fancy that!
Air Force Secretary Stuart Symington was an old drinking buddy of Harry Truman from the Pendergast political machine in Missouri and friends with the folks who ran Convair. Symington KNEW the XB-35 was far superior to the XB-36 and some say he was responsible for the government supplied components and assemblies (gearboxes and propellors) that gave the -35 such headaches.
One final thing: the XB-35 cost a lot less than the XB-36 in both prototypes and projected production run of 200 airframes.
Jack Northrup and the rest of the Free World got screwed by this magnificent aircraft being strangled at birth.
Do you have any comments?
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