Talk:Bell X-1/Archive 1

Untitled
Under first flight it claims January 19, but in operational history it has that Wollams first flighht was January 25. This Day In Aviation lists the plane's first flight as January 25. Where is the January 19 date from? I can't corroborate thhat day anywhere outside Wikia. — Preceding unsigned comment added by 2603:9000:C006:63EE:D808:2EDF:99BE:B4A7 (talk) 18:30, 16 January 2021 (UTC)

Captain Brown RN was the pilot designate for the M.52 and wrote a book, Miles M.52, Gateway To Supersonic Flight. He makes a number of claims in his book regarding the X-1.

To wit, quote #1: The X-1 had a tailplane adjustable in incidence for trim purposes, with a conventional trailing edge elevator.

My comment: Correct. The specification supplied to Bell specified that the XS-1 be equipped with a movable horizontal stabilizer to provide pitch (nose up or down) control when shock waves made the elevators ineffective and spelled out also the rate of movement (one degree/second). Captain Brown also notes the X-1 as built "incorporated none of the design features of the Miles M.52."

Quote #2: Yeager lost control when flying at Mach 0.94 ... . Both he and the engineers thought that was the end of the road. Magically a solution was provided by Bell almost instantaneously, in the form of a "field fix" variation of the "flying tail" encountered on the U.K. visit to Miles. Bell's control solution was to use the pre-existing tailplane trimmer to modify the incidence of the tailplane in flight, by means of a switch in the cockpit. Two flights after evaluating their ad hoc "flying tail," Yeager attained supersonic flight.

My comment: Not so. Bell did not change anything; see comment to quote #1. Yeager has always given the project flight engineer Jack Ridley the credit with coming up with the idea to use the tailplane trim as a means of pitch control during the period when the elevator lost effectiveness. Ridley, however, just had his finger on the pulse with respect to the papers crossing his desk, IMHO. The ability to control pitch with stabilizer in the transonic regime was investigated by Axel T. Mattson in his paper NACA RM No. L7A03 "FORCE AND LONGITUDINAL CONTROL CHARACTERJSTICS OF A 1/16-SCALE MODEL OF THE BELL XS-1 TRANSONIC RESEARCH AIRPLANE AT HIGH MACH NUMBERS" (May 21, 1947).

Quote #3: When the X-1 ran into compressibility problems in 1947 it was rescued by fitment of the "flying tail."

Quote #4: The British aviation fraternity is firmly convinced that the Bell X-1 owed its success to what the Americans gleaned from their visit to the Miles factory in Autumn 1944, and in particular what Bell learned from the M.52's "flying tail." Certainly, in spite of American protestations that they had their own original ideas on a "flying tail," there does not appear to be any solid evidence of its appearance on test before the X-1 ran into transonic trouble in 1947.

Quote #5: On seventh flight, after "flying tail" has been fitted to the X-1, Yeager attains controlled supersonic level flight, Mach 1.02.

Quote #6 (From the “Guild News”, June 2009): The Americans will not admit that the flying tail which was on the M.52 was what let the Bell X-1 break the sound barrier. Chuck Yeager had run into severe compressibility trouble at Mach .94. In fact, General Albert Boyd, head of the Flight Test Division at Wright Patterson AFB, had said, "Well, fellers, this is the end of the road." Then three days later Bell came charging down with this all-flying tail, designed by a guy who had been to Woodley and had seen the tail on the M.52. He'd done some work on it, but basically it was the M.52's tail, which he admitted more or less on his deathbed. They popped it straight onto the X-1 there and then, and it did the trick.

My comment: It's interesting how Captain Brown's narrative changes from that given in #2 to that in #6.

Yeager's flight test report following the first supersonic flight:

Date: 14 October 1947 Pilot: Capt. Charles E. Yeager Time: 14 Minutes 9th Powered Flight

1. After normal pilot entry and the subsequent climb, the XS-1 was dropped from the B-29 at 20,000' and at 250 mph IAS. This was slower than desired.

2. Immediately after drop, all four cylinders were turned on in rapid sequence, their operation stabilizing at the chamber and line pressures reported in the last flight. The ensuing climb was made at .85 - .88 Mach, and, as usual, it was necessary to change the stabilizer setting to 2 degrees nose down from its pre-drop setting of 1 degree nose down. Two cylinders were turned off between 35,000' and 40,000', but speed had increased to .92 Mach as the airplane was levelled off at 42,000'. Incidentally, during the slight pushover at this altitude, the lox line pressure dropped perhaps 40 psi, and the resultant rich mixture caused the chamber pressures to decrease slightly. The effect was only momentary, occurring at 0.6 Gs, and all pressures returned to normal at 1 G.

3. ln anticipation of the decrease in elevator effectiveness at speeds above .93 Mach, longitudinal control by means of the stabilizer was tried during the climb at .83, .88, and .92 Mach. The stabilizer was moved in increments of 1/4 - 1/3 degree and proved to be very effective; also, no change in effectiveness was noticed at the different speeds.

4. At 42,000' in approximately level flight, a third cylinder was turned on. Acceleration was rapid, and speed increased to .98 Mach. The needle of the machmeter fluctuated at this reading momentarily, then passed off the scale. Assuming that the off-scale reading remained linear, it is estimated that 1.05 Mach was attained at this time. Approximately 30% of fuel and lox remained when this speed was reached and the motor was turned off.

5. While the usual light buffet and instability characteristics were encountered in the .88 - .90 Mach range and elevator effectiveness was very greatly decreased at .94 Mach, stability about all three axes was good as speed increased and elevator effectiveness was regained above .97 Mach. As speed decreased after turning off the motor, the various phenomena occurred in reverse sequence at the usual speeds, and in addition, a slight longitudinal porpoising was noticed from .98 - .96 Mach which (was) controllable by the elevators alone. Incidentally, the stabilizer setting was not changed from its two-degree nose-down position after trial at .92 Mach.

6. After jettisoning the remaining fuel and lox, a 1 G stall was performed at 45,000'. The flight was concluded by the subsequent glide and a normal landing on the lake bed.

Yeager's presentation at the first XS-1 conference, 9 January 1948:

As the Mach number was increased from .87, the buffeting became more severe, and a nose down trim change was noted. The forces were quite light, and the movement of the control column remained the best means of indicating the trim change. At approximately .90 Mach number trim change previously mentioned reversed, and the tendency was for the nose to rise and, in the range of approximately .92 Mach number, the buffeting became quite severe.

At this point in the program it was decided from a correlation of model test data that the one degree per second actuator for the stabilizer might prove to be too slow for proper control during subsequent flights, and an interruption in the program was made to install a faster motor. In the first flight after the new stabilizer actuator was installed, the Mach number was increased to .94. At this point, the trim change again reversed to a nose-down tendency, but it was still easily controllable and approximately 3degree of up elevator provided level flight. From .94 to .96. the elevators and rudder became increasingly ineffective until, at the latter figure, they could be moved throughout their range of displacement with very slight response from the aircraft. At approximately .95, the buffeting decreased rapidly and became non existent at .96.

Up to this time a stabilizer setting of 2degree leading edge up was used in all of the high-speed test runs. The next flight was therefore initiated to investigate the effectiveness of control by the stabilizer at the higher speeds above .96 since the setting had only been varied in climbs up to this time. As the speed was increased on this flight, the stabilizer was changed to 1degree leading edge up and returned to 2degree leading edge up successively at .84, .88, and .95 Mach numbers. The acceleration experienced in the cockpit was approximately the same for all speeds, and it was decided that the stabilizer was still effective, even though the elevator and rudder had lost their effectiveness. The ailerons remained effective throughout the range. With the stabilizer setting of 2degree, the speed was allowed to increase to approximately .98 to .99 Mach number, where elevator and rudder effectiveness were regained and the airplane seemed to smooth out to normal flying characteristics. This development lent added confidence, and the airplane was allowed to continue to accelerate until an indication of 1.02 on the cockpit Mach meter was obtained. At this indication, the meter momentarily stopped and then jumped to 1.06, and this hesitation was assumed to be caused by the effect of shock waves on the static source. At this time the power units were cut and the airplane allowed to decelerate back to the subsonic flight condition.

My comment: Of particular note is that the program was interrupted in order to install a faster trim motor, not to install a "flying tail," as insisted by Captain Brown. The X-1 retained the stabilizer/elevator system as spelled out by Captain Brown in quote #1 throughout its life and was never modified for the supersonic flight, as a reading of Yeager's reports above confirms.

Captain Brown, in his book, calls the M.52 tail a "flying tail," and it was what would be called a "slab" today, a unitary piece with no separate stabilizer/elevator. Here is where I feel the problem lies. NASA and Yeager, even to this day, refer to the X-1 trimmable stabilizer and elevator setup as a, you guessed it, "flying tail." Two contemporaneous aircraft, the D558 and the F-86A, both had the same setup as the X-1 (trimmable tailplane with elevator). It seems to me to be a case of two countries separated by a common language. Has Captain Brown merely misunderstood the U.S.A.'s use of terminology? I can think of no other explanation, because the plain fact is, the X-1 tail never underwent modification from the day it was built, other than the trim motor.

It would be interesting to have interviewed Captain Brown to gain an insight into why he had the idea that the X-1 tail was modified. babraham AT netspace.net.au — Preceding unsigned comment added by 203.7.51.96 (talk) 18:54, 26 March 2016 (UTC)

X-1 or X-1 Series?
To cut to the chase, this article is a mess. I'd like to start working on it, but before I do, there needs to be some clarification -- what's the intent: does this article, Bell X-1 describe the entire X-1 series of aircraft, or simply the X-1 type (S/N's 46-062, 46-063 and 46-064)? As the X-1A, X-1B, X-1D and X-1E (063 rebuilt) are different than the original X-1, they deserve some sort of differentiation, either through separate articles or sections on this page. Mustang dvs 04:45, 3 December 2006 (UTC)
 * Not to mention that the third XS-1 is completely ignored. Mustang dvs 04:48, 3 December 2006 (UTC)
 * I decided to follow the X-24 example, which covers both versions. (Although the argument could be made that the X-24 was a single aircraft, with multiple configurations, whereas the X-1 was a series of aircraft incorporating entirely separate variants.) Mustang dvs 17:34, 3 December 2006 (UTC)

Other Sound Barrier Claims
I've almost finished my contributions to a new article on George Welch. IMHO, he has one of the best challenges for first supersonic flight (supposedly 1 week before the X-1, also at Murdoc Field aka Edwards AFB). Should he be included here? My feeling is that if we are gonna include Guido Mutke we should also include him, but i'm reluctant to make such a controversial contribution to a major article which I haven't had a hand in shaping. -Lommer 06:44, 18 Oct 2004 (UTC)


 * Mutke's claim is nonsense. The 262's terminal velocity was less than the Spit's. (By the way, likely a typo, it's Muroc, N Murdoc, after the dry lake {(ult after a guy named Corum, or so I understand}). Trekphiler 23:57, 5 December 2005 (UTC)


 * Yep, it is Muroc (see Edwards Air Force Base for more). But anyways, IIRC, spitfire pilots had reported symptoms similar to supersonic flight (mostly mach tuck and jump) during steep dives, so I don't think that rules out Mutke's claim. Also you have to consider Terminal Velocity in a full power dive, not in a free dive. I'm not certain, but I suspect a 262's TV would be higher in that scenario. -User:Lommer | talk 21:20, 7 December 2005 (UTC)


 * Does all that "information" need to be included in this article? None of it is referenced, most of it is rumor and some of it doesn't even make sense as it's currently written: "The mysterious 702 mph Me-163B by Dittmar flight is wrapped in mystery and has no Mach number associated with it." At the very least, it should be it's own section, somewhere later in the article than in the intro; it might even deserve it's own page. Mustang dvs 04:45, 3 December 2006 (UTC)


 * P-38 pilots reported much the same, & it wasn't supersonic, it was compressibility; see Caidin, Fork-Tailed Devil. As I understand TV, it's measured at full power; it reflects the max vel the airframe is capable of. (I stand to be corrected there.) Trekphiler 03:49, 12 April 2007 (UTC)

Merge Request → Sound barrier
Since most of the supersonic disputes are covered (very similarly, I might add) in sound barrier, and really have no bearing on the X-1 history, I believe that they should be moved to/merged with that article. Mustang dvs 23:16, 3 December 2006 (UTC)

Jack Woolum and Slick Goodlin
This article makes no mention of Jack Woolum or Slick Goodlin, who flew the X-1 long before Yeager got attached to the project. Logawi 15:09, 25 November 2005 (UTC)
 * Not to disparage either man's flying skills, but Woolum only flew the plane as a glider, and Goodlin never got it up above Mach 0.8, when the plane was intended to research transonic and supersonic phenomena. Yeager was the one who did the important things with the plane, and so he's the one who gets the most information. Iceberg3k 20:13, 2 February 2006 (UTC)
 * Yeager wouldn't have had the chance to fly the X-1, had it not been for Jack Woolams  or "Slick" Goodlin. The fact that they weren't the pilots who gained notoriety from the X-1's most famous flight doesn't make them any less important to the history of the X-1. In fact, were it not for Woolams, the X-1 program would never have been moved to Muroc. Mustang dvs 23:19, 3 December 2006 (UTC)

XS = extra-sonic?
Trekphiler just added a bit that says "XS" originally stood for extra-sonic. I've never heard this before. Can anyone provide sources? -User:Lommer | talk 21:22, 7 December 2005 (UTC)
 * XS stood for "Experimental, Supersonic." Designating the goal they wanted to reach with it. Iceberg3k 14:05, 14 December 2005 (UTC)
 * That makes a lot more sense. Thanks. -User:Lommer | talk 19:29, 14 December 2005 (UTC)

Extra-Sonic would mean outside sound. Even for the military, that makes too little sense.
 * I've heard it said; I don't vouch for it. (My understanding was, it meant "past sonic", for which it makes some sense.) Trekphiler 03:52, 12 April 2007 (UTC)

Image problem
at 20:09, 29 March 2006 (UTC), there are two images that are not showing up. GregCovey 20:10, 29 March 2006 (UTC)

What is a stab?
--Gbleem 20:30, 24 June 2006 (UTC)
 * It means 'stabilator', the horizontal tail section. Since supersonic flight alters the center of lift of the main wing, you need to adjust the trim of the tail in order to offset the nose-heavy condition that occurs-- more than elevator deflection alone will provide. You need to re-adjust the whole horizontal tail section, the 'stab', to do this.

Miles connection in History?
What happened to the mention of the Miles M-52. The influence it had on the X-1 might be controversial, but it is an interesting historical note to make surely? Maybe Bernard Biales can provide his reasoning for editing these facts out. Meio 18:20 GMT, 12 July 2006.
 * The straw-man argument in the article "Many believe..." needs to be substantiated with a reference or modified/deleted. The aircraft had similar missions and were designed using similar engineering resources -- of course they were going to look similar. Mustang dvs 04:45, 3 December 2006 (UTC)
 * I've seen a TV doc claiming Miles' data was passed to Bell's team, including the all-flying tail, without which (the doc claims) X-1 would never have succeeded. Trekphiler 03:54, 12 April 2007 (UTC)
 * I have added the cites and re-introduced the facts into the article. Twobells (talk) 18:47, 21 June 2013 (UTC)
 * Someone has tried to delete legitimate cites from the article, that is completely unacceptable. Twobells (talk) 20:42, 21 June 2013 (UTC)

Miles / Bell and the variable tail plane
A program on this subject recently aired on Discovery Wings (UK) stated that the variable tail plane was built onto the Bell X-1 - but originally fixed in place. IIRC It was only after initial flights, that Bell decided to try making it adjustable in flight. Can anyone expand on that? Regards, Lynbarn 16:26, 7 February 2007 (UTC)


 * The M.52 tail was a relatively primitive affair compared to the Bell's post-flight redesign. 87.113.23.176 11:04, 28 September 2007 (UTC)


 * This primitive primitive Miles pitch control, is the nowadays common full moveable tailplane, much more advanced as the X-1 tail plane. The Bell X-1 use the all moveable trimmable tailplane design used by the Messerschmitt Me 262. --HDP (talk) 09:14, 18 November 2008 (UTC)
 * Wrong, the Miles M52 moving tail design is what was used on the X-1. The M-52 tailplane originally was STUCK straight on to the X-1 until a later re-design and we all know how easy it is to RE-design something once the concept has been proven. As for being 'primitive' it was good enough to be the first technology that allowed planes to fly at a supersonic speed.Twobells (talk) 21:31, 20 July 2014 (UTC)


 * There's a 1946 Flight article on the Miles M.52 here; Miles on Supersonic Flight


 * BTW, the M.52 was designed to do 1,000mph, not just break the sound barrier. —Preceding unsigned comment added by 86.112.68.219 (talk) 11:39, 31 March 2011 (UTC)


 * A 1956 lecture by Charles Yeager to the Royal Aeronautical Society in which he gives details on the X-1 and his flights, here:

Date Contradiction or Time Machine?
Am I reading this right that the article says the X-1 was contracted in March 1946 and the first flight occurred in January 1946? Holy crap! The X-1 was a time machine!!! Pjbflynn 22:19, 5 February 2007 (UTC)


 * Doubtless a misprint. Trekphiler 04:01, 12 April 2007 (UTC)

Give me a lift
I deleted
 * "In all earlier claims, the sound barrier was supposedly breached by diving aircraft and thus making it impossible to determine if aerodynamic lift could be maintained at those speeds."

It's unclear what was meant; & "supposedly breached" is factually inaccurate (engineers knew the difference between compressibility & sonic speed, even if media nitwits didn't; cf claims for DH 108 & Geoffrey deHavilland); & I'm unaware of doubt "aerodynamic lift could be maintained" (more like, could airframes survive the stresses), but I claim no expertise. It needs a rewrite, in any case, if only to source who doubted lift capacity. Trekphiler 04:01, 12 April 2007 (UTC)

Question
In the movie the "Right Stuff," observers on the ground during Yeager's first flight through the sound barrier are seen dejected after hearing the sonic boom and assuming that the X-1 had crashed. Is there any truth to this? Did the pliots and engineers not know that a faster-than-sound aircraft would produce a sonic boom? —The preceding unsigned comment was added by Jaedglass (talk • contribs) 20:12, 8 May 2007 (UTC).


 * If I remember right, Chuck TYeager has stated the ground crew did not hear the sonic boom because the X-1 was too far away. THe scene is dramatic licence, typical of fictionalized accounts, not just in Hollywood. Shakespeare made great use of the technique. - BillCJ 00:47, 1 August 2007 (UTC)

Designed by miles engineering (sic)
If someone has a credible, verifiable source that proves that Miles Aircraft (I assume this is what the user meant) did the primary design work for the entire X-1, then by all means cite it. (Assuming that the edit was not vandalism, which is not entirely clear.) Almost all early US jet engines were British built, licence-bulit versions of British-designed engines, or developments of British designs. No one is trying to suppress that. In addition, the British gave us 3 invetions (angled deck, mirror landing system, and steam catapult), thaat made modern jet carrier aviation possible. (Then they invented the harrier, which didn't need any of these!) If there is legitimate proof that Miles played any role in the X-1's development, I don't see what that would need to be suppressed. I'm going to start watching the Wright Flyer page now, just to make sure this user doesn't claim they stole THAT from the British too! - BillCJ 00:47, 1 August 2007 (UTC)


 * It wasn't stolen, it was shared freely. Since we Brits foolishly abandoned the Bullet-shaped thin-wing design in favour of a Delta (copying the Germans) we gave our now uneeded information (designs, sketches and even the fuselages of prototype M.51 and an M.52) to the Americans for free, with the expressed intention that any and all information be shared if the design successfully went super-sonic. Some design changes took place in the 'States: The tail was re-designed and the jet was replaced with a rocket and, ultimately, it went super-sonic. Bell was prepared to honour it's side of the agreement to share the data, but the USAF stepped in and claimed the project as a State Secret, and Bell was not allowed to give any information back to Britain.
 * It's a good example of engineers from both countries being bossed around by the government superiours, with no experience with the technology. In Britain, people with no aerospace knowledge abandoned the M.52 because they thought the Germans must have been right, and in the 'States, the government essentially forced Bell into stealing the earlier British work.
 * Miles shold DEFINATELY be credited. It's part of aviation hererige. 87.113.23.176 11:05, 28 September 2007 (UTC)
 * Plus, while we're hovering around the subject, a Brit flew a plane in New Zealand before the Wright Flyer... He flew farther for longer and higher... but he crash-landed and the flight was not considered a success. The Brother's knew more of what there machine could get away with and didn't try to push it too far. 87.113.23.176 11:05, 28 September 2007 (UTC)


 * What nonsense about the Miles M.52, long since dispatched as urban mythology. If you want to keep up this line of supposition, feed it it into the Miles M.52 page. New Zealander inventor Pearce may have flown, but it was a more of a trajectory than a flight. Control is the aspect that was missing. Anyone could launch a device but that is not flying. FWIW Bzuk 11:14, 28 September 2007 (UTC).


 * Urban mythology? Hell, read the wiki page for the M.52. The fact that it's such a similar design, based on the 50-cal browning, and it was designed first help to corroborate what I'm saying. I don't understand why you seem to find it so offensive to have the M.52 credited on this page, it's part of aviation history and it's yet another good example of trans-atlantic cooperation.


 * Also, while It may not have been controlled flight, it was still powered and heavier-than-air. I'm not trying to take anything away from the Wright's achievement at all, they were still the true farthers of aviation.87.112.23.117 09:13, 29 September 2007 (UTC)
 * There is a well documented lineage for both the Bell X-1 and Miles M.52. I suggest you find some authoritative sources to corroborate your statements, otherwise, my comments stand. There is no scientific basis for Pearce's claim and I know his biographer who has never suggested that the hop into a bush was anything other than an abortive flight attempt. You could throw the Russian claims and Langley's steam contraption into the same category. FWIW Bzuk 12:24, 29 September 2007 (UTC).


 * Fair point. I'll dig up some refferences. Thanks for the brief debate though, you definately know your stuff... 87.113.9.63 19:15, 29 September 2007 (UTC)

http://www.aero-web.org/specs/bell/xs-1.htm

I'll find some more links later, or you can Google and Yahoo yourself... If I get more time, I'll put some more up. —Preceding unsigned comment added by 87.112.23.191 (talk) 15:30, 3 October 2007 (UTC)


 * The site you have provided does not give a correlation to Miles engineering antecedents. The quote; "Many believe the X-1 was heavily based on the British designed Miles M.52 jet. The Miles M.52 was strangely cancelled by the British government months away from a test flight, and all technical data regarding it was transferred to Bell. Later tests show that the Miles M.52 would have broken the sound barrier if allowed to fly." is extremely doubtful in origin; it's only the author's opinion?! see the weasel words used. FWIW Bzuk 15:42, 6 October 2007 (UTC).
 * Also FWIW, I don't think the M.52 ref should be del entirely, if only for those (like me) who've heard the claim the flying tail enabled the XS-1 to go sonic & was owed to the M.52, but know no more about either. (I'd never heard of the M.52 before that.) My $0.02. Trekphiler (talk) 20:31, 23 March 2008 (UTC)
 * If you read the article on the M.52, the claim is made there at least more substantially. Whether the British gave away the secret of the "flying tail" or it was "stolen?!" can be introduced into the X-1 article but the entry does need to be submitted with proper authentication and attribution. FWIW Bzuk (talk) 13:08, 24 March 2008 (UTC).


 * It needs to be mentioned that the all-moving tailplane was a BRITISH design, first used on a Miles Falcon in 1943. This must be added to the article, as it just is not fair to let the British engineers go without due credit. —Preceding unsigned comment added by Mrjake2002 (talk • contribs) 15:25, 9 September 2008 (UTC)


 * Eric "Winkle" Brown says in his book 'Wings on my sleeves' that he flew the first all moving one fitted to a subsonic plane (Spitfire I think), well before it was used on the X-1, as part of the research on the M.52. I'll try and dig up the reference next weekend. The X-1 was the first to fly it supersonically (obviously), but the idea seems to have been used first in the UK. Eric Brown is pretty reputable. I don't think there's any secret about why the M.52 was cancelled- the British government was flat broke after WWII. I'm also sure that there wasn't any particular subterfuge involved on the part of the Americans, just the normal bloody-minded bureaucratic screw-up.- (User) WolfKeeper (Talk) 16:29, 9 September 2008 (UTC)

Unless I am greatly mistaken, the X-1 did not use an "all-moving tailplane", but a variable-incidence tailplane with elevators. (It's possible this was in one of Yeager's books, but I'm not certain.) I also seem to recall that this type of tailplane had been developed in the 1930s, tho I don't remember by whom. Since I don't have reliable sources to cite this, I'm not adding it to the article as yet. It doesn't matter to me who invented what when, just that if it is in the article, it be cited correctly from reliable sources, which blogs are decidedly not. - BillCJ (talk) 17:01, 9 September 2008 (UTC)


 * IRC they locked out the elevators and used a screw jack to adjust the angle of incidence of the tailplane. The stuff about the M.52 design using this type of tail is pretty well established (e.g. ) specifically to avoid the control issues due to the movement of the shockwave in transonic flight, and it was actually flown at ~Mach 0.86. There's also clear evidence that there was technology transfer. Of course the X-1 project could have known about it before the transfer occurred, but there's no mention of it before that point in any documentation that I'm aware of prior to the cancellation of the M.52; and at some point it was fitted to the X-1, whereas the M.52 had it all along.- (User) WolfKeeper (Talk) 17:30, 9 September 2008 (UTC)


 * The UK term for such as tailplane is an 'all-flying tail', because the whole tail surface moves pivoting about a central point roughly at the mid-chord position, as opposed to just the elevators which are hinged to a fixed point, i.e, the tailplane, and IIRC the US term is 'stabilator'. The English Electric P.1 had one from the start back in 1947. This type of tail was also used in the later F-86G in place of the earlier tailplane/elevator-type tail. WolfKeeper is correct in that the initial Bell X-1 used the tailplane trim to control the aircraft in pitch while transonic, however the all-flying tail later became just about standard on all transonic and supersonic designs. —Preceding unsigned comment added by 213.40.250.73 (talk) 20:41, 23 October 2009 (UTC)

I have added new legitimate cites that details how the Air Ministry and the US government brokered an agreement to share research on supersonic flight and develop a plane from it, subsequently the US citing 'security' then proceeded to renege on their side of the bargain once they had the all the data and a fully working stabilator prototype (which Bell initially stuck onto the X-1) Twobells (talk) 20:54, 21 June 2013 (UTC) Here are just two from one of the most legitimate sources in the history of flight: Wings on My Sleeve: Captain Eric Brown The Miles M.52: Gateway to Supersonic Flight and one from J Miller who covers the transferred data, prototype and agreement in his 'XPlanes' book. [http://www.amazon.com/The-X-Planes-X-1-X-45-Edition/dp/1857801091 Miller, Jay. The X-Planes: X-1 to X-45. Hinckley, UK: Midland, 2001. ISBN 1-85780-109-1.]


 * Twobells, I believe that this article needs a wider sampling of books than just two Brown books and one from Jay Miller in the UK. The problem with these books is that the assertion that Bell used data from the Miles M.52 program is questioned by some historians and absolutely contradicted by Richard P. Hallion, who points out that the Bell X-1 was flying before the M.52 was canceled. In "Toward Mach 2", page 69, Hallion says the notional Miles M.52 influence on the Bell X-1 is "an utter myth." Hallion describes a British documentary about the notion, a film which had "a lot of flaws". Hallion says the US had already investigated the all-moving tail in the Curtiss XP-42, and noted in mid-1944 that this tail would be needed for very high speed flight.
 * Until someone is able to write a completely neutral account of the various theories of technology transfer, this article cannot host a single version, especially one which is totally denied by Hallion. Binksternet (talk) 02:48, 23 July 2013 (UTC)
 * First of all Jay Miller is an American aviation expert and historian, considered one of the very best in the field. re: Hallion, unfortunately the weight of evidence is against him, something that you will have to accept, the facts need to be included in the article ensuring that the edits are neutral, we cannot dismiss the weight of evidence purely because it doesn't suit a certain viewpoint. In closing, the X-1 did 'fly' for very short periods before receiving the M.52 data and stabilator; however, the crucial fact is that the plane was not stable, it was only the data and stabilator from the M.52 that gave the plane air worthiness, a contribution much like Donald Davies's packet switching was 'absorbed' by DARPA. I suggest credit be given in the article, it does not dismiss the achievements of Bell one iota but once again confirms that the US/UK are greater than the sum of their constituent parts. Twobells (talk) 11:19, 25 July 2013 (UTC)


 * Given that no attempt to be neutral in regard to the alleged technology transfers and opposing views, I've removed the section. Please don't readd this until there is consensus here to add a neutral and balanced version. - BilCat (talk) 22:20, 19 September 2014 (UTC)
 * You are using a strange argument for deletion user [User:BilCat|BilCat]], these are just the facts as verified by both American and British sources which are eminently neutral, if you have an issue with the wording then please just edit the article to a version that you find personally more suitable but the delete the entire section on the grounds that it is not 'neutral' while at the same time not describing why it isn't neutral makes no sense whatsoever. Twobells''t@lk 11:24, 3 May 2015 (UTC)
 * I agree with the removal of the text inserted by Twobells which was far too positive about the influence of Miles Engineering. Binksternet (talk) 12:52, 3 May 2015 (UTC)
 * Too 'Positive'? Where does it say in Wikipedia that an article's citations mustn't be 'too positive'? As editors we cannot help that the facts were 'positive'. Please refer me to that section. Surely, as editors we are seeking neutrality, deleting verified citations confirming both American and British aviation historians whom I might add recorded the statements by the various people actually involved on video, radio and via the original Miles-Bell documentation, which we can all see for ourselves, as well as all the aviation experts research suggest's a complete lack of neutrality. As I stated elsewhere, if an editor feels that the facts surrounding the M-52 technology transfer can been challenged then please by all means include that in the design section with the associated citations but to completely remove the entire section on the basis on one counter source against multiple 'pro' sources is 'cherry picking'. Twobells''t@lk 18:17, 3 May 2015 (UTC)
 * The trouble with this claim is that the X-1 never flew with a stabilator. This much can be confirmed from photographs, including those taken on the day of the first supersonic flight. It has conventional elevators. Jamesdmay (talk) 07:44, 31 October 2022 (UTC)

design
Should the design section include that whole information exchange fiasco between the UK and the US? - - - BigglesPiP  - Talk 02:49, 23 May 2008 (UTC)
 * Yup, this is the only article that does not note the British contribution, in that the X1 was an exact copy of the M-52 and even then England had to supply the movable tail when the US design had stability issues. I will update the article when I have time. Twobells''t@lk 10:21, 3 May 2015 (UTC)


 * Given that no attempt to be neutral in regard to the alleged technology transfers and opposing views, I've removed the section, again. Please don't readd this until there is consensus here to add a neutral and balanced version. - BilCat (talk) 10:34, 3 May 2015 (UTC)
 * With respect you are once again using the same suspect argument you employed last year see here you say that the section is not 'neutral' but refuse to explain why you don't think it is neutral, the section includes verified citations from both the US and UK as well as all the other wiki articles which all reflect the M-52 and X-1's lineage, it is only this article that seemingly refuses to accept the historical collaboration of the project and I really do not appreciate you deleting talk history which included the citation's as well as the PBS video for anyone interested in the project. So once again hoping that user BilCat won't delete this here is the NASA NOVA PBS video: https://www.youtube.com/watch?v=6tjits7Y-zU along with the transcript and Jay Miller's wonderful book on the subject Twobells''t@lk 11:28, 3 May 2015 (UTC)
 * You cannot ignore Hallion and others who question or completely deny any influence by Miles Engineering. You are picking and choosing your sources to focus only on those that agree with your preferred version. Until you compose a properly balanced block of text I will agree with the removal of your contributions. Binksternet (talk) 12:56, 3 May 2015 (UTC)
 * Hallion again? He is in the minority compared with the vast balance of authority covering the M-52 and X-1's lineage which is very well documented, if you wish me to include a sentence stating that Hallion denies the technology transfer then I will if you supply me with the necessary citation. As for 'others', as far as I know the balance considerably favours the accepted development chronology among aviation experts; however, if you can find any other sources that deny the technology transfer including the stabilator please supply them and I will add them to the article. In closing, we cannot in all fairness make absolutely no mention of the British contribution on the basis of one author while ignoring the numerous other authors who validate that same contribution, surely that is 'cherry picking' is it not? Twobells''t@lk 18:00, 3 May 2015 (UTC)

Data compressibility
While I claim no expertise in aerodynamics, the connection between compressibility problems, the variable-incidence tailplane, & sonic flight strikes me a bit thin. Recovery in compressibility conditions, yes, but given the aircraft was capable of level sonic (or near-sonic) flight, keeping level, or dive recovery, wasn't a problem (as it was in the P-38, for instance). Am i missing something? TREKphiler  hit me ♠  01:46, 13 September 2008 (UTC)


 * Yes you are;


 * Perhaps the simplest explanation for a layman is this: As an aeroplane approaches the speed of sound, Mach 1, the compression of the air (due to the aeroplane moving through it) creates shock waves that buffet the aircraft. Then, as the speed increases further, the effect of the shock waves is to move the centre of pressure (lift) backwards towards the tail, changing the balance of the aircraft so that it becomes nose-heavy, and wants to dive. To counteract this, the pilot must pull back on the control column to raise the elevators and prevent the nose from dropping. As speed increases still further, there comes a point where the pilot can no longer hold the nose of the aeroplane up, and the aircraft then starts to do what is called a 'bunt' - a downwards half-loop. It is at around this point where the pilot can no longer stop the nose from dropping that the Critical Mach Number is usually measured.


 * In the days of the last piston-engined fighters and the first jet fighters these sorts of speeds were only capable of being reached in a dive, and with the controls all manually operated, a pilot's physical strength had a degree of bearing on when he could no longer prevent the nose from dropping below the intended flight path (i.e., steepening the dive), hence a strong pilot would be able to endure a higher speed in a dive compared to a physically weaker pilot. So the Mcrit is not really a fixed figure for these aircraft, it's more of a guideline and is usually based on the abilities of the 'average' service pilot. The problem here of course, is that the aeroplane is already diving, so that any steepening of the dive actually increases the airspeed due to the effects of gravity. When this happens the pilot is faced not only with a loss of control, but with a steadily worsening strain on the airframe, which may well cause it to break up. The only good point about these dives was that as the aircraft descended to lower altitudes, the air was warmer and the speed of sound (Mach 1) rose relative to airspeed, so that eventually the shock waves dissipated - the speed of sound in air is lower the higher you fly - it's about 660 knots at sea level. This was the problem that was known in aviation circles in the late 1930s/1940s as the Sound Barrier. Transonic and supersonic aircraft don't have a Critical Mach Number, as they are expressly designed to be able to be controlled at and above the speed of sound.


 * Incidently, this backwards-moving of the 'balance' of the aeroplane occurs in all aircraft that go through the 'sound barrier' and in the case of the Concorde supersonic airliner, the balance of the aeroplane was maintained by pumping fuel from tanks at the front of the aircraft to tanks at the rear when going supersonic. This procedure was then reversed when slowing down to below the speed of sound.


 * In short, when an aeroplane reaches the speed of sound, it's 'balance' changes and it wants to dive. In order to stop it diving and make it continue in a straight (horizontal) line, the pilot must raise the elevators to counteract the change in trim. When the amount of additional trim available from the elevators is used up - i.e., the pilot has the stick back as far as it will go just to keep it flying in a straight line - the pilot cannot then prevent the aircraft from nosing down into a dive. That means the aeroplane at that point is, in effect, no longer fully controllable. The adjustable tailplane/all-flying tail solves this problem, as they both posses much greater amounts of (trim) movement than is possible with an elevator alone.


 * It was for this reason of control that tailless designs such as the DH 108 were tried in early high-speed tests, as it was thought that they would suffer less from the compressibility problems experienced by conventional tailed designs, although unfortunately, the reverse proved to be the case. —Preceding unsigned comment added by 86.112.50.65 (talk) 10:52, 22 March 2011 (UTC)
 * That helps a lot, thanx. I didn't realize the pitch change was so large. :o  TREKphiler   any time you're ready, Uhura  13:30 & 13:31, 22 March 2011 (UTC)


 * You're welcome.


 * BTW, the reason that an 'all-flying' tail was later used is because of a shock wave forming at the leading edge of a conventional tailplane as the aeroplane approaches Mach 1. As speed increases still further this shock wave moves rearwards along the tailplane until it eventually reaches the elevator hinge line. At this point all elevator control is lost, as the control surface is effectively shielded from the external airflow by the shock wave. Hence the Bell X-1 pilot having to resort to using the trimmable tailplane, as by then the elevator would have become ineffective. The 'all-flying' tail has no hinge line so remains effective at transonic speeds. —Preceding unsigned comment added by 86.112.83.135 (talk) 15:29, 22 March 2011 (UTC)
 * I understood the flying tail had benefits of improved authority (& simplicity), but I'd never have guessed it was essenital. Funny thing is, I was reading just yesterday about the Concorde & F-106 using fuel transfer due to problems in the transonic range... :o (You didn't have anything to do with that, did you? ;p)  TREKphiler   any time you're ready, Uhura  17:19, 22 March 2011 (UTC) (P.S. There's some really well-informed people over there. I just wish I could get more of them to use their sources here, too. :


 * Concorde (and presumably the F-106) used the fuel transfer method because it is less aerodynamically inefficient than the additional drag caused by flying with the elevators/elevons permanently deflected up to counteract the change in trim. Because Concorde was designed as a commercial airliner it had an awful lot of very careful design put into it, so as to make it efficient enough for an airline to make money with, something that military operators don't have to worry about. So using the fuel transfer method saved drag, and therefore fuel, and therefore costs, which was important for the operator. I don't really know much about the reasons for the F-106 using the system.


 * ... and no, I don't have anything to do with the other linked site. If you are interested in this sort of thing (Aerodynamics) then I would suggest you try and get hold of a book called Mechanics of Flight by A.C. Kermode. It was first published in 1932 and has been updated ever since, so it will still be current. It's full of formulae but still very readable by the layman, even if maths is not your strong point. Try your local library if you can't find it anywhere. —Preceding unsigned comment added by 86.112.83.135 (talk) 19:16, 22 March 2011 (UTC)
 * No, it was a long shot you were connected. :D It was a mighty coincidence, tho.
 * Thx for the source. I'm always looking for good info. (More than my budget allows, usually. :(p )  TREKphiler   any time you're ready, Uhura  19:25, 22 March 2011 (UTC)


 * I don't know what part of the world you're in but if there is a local lending library near you then they will probably be able to order it for you, which shouldn't cost more than a few pence/cents. Before I bought my copy around 1990 my local library got me a copy sent from the library at (what was then) the RAE at Farnborough. —Preceding unsigned comment added by 86.112.83.135 (talk) 20:07, 22 March 2011 (UTC)
 * Oh, no. If they can find it (& IDK if the interlibrary loans go out of country), it doesn't cost anything, usually. (There is a fee for special stuff, but I've never actually had to pay it.) I meant, I'd much rather own it than just read it. ;p That's my biggest weakness, even worse than potato chips. :o  TREKphiler   any time you're ready, Uhura  20:21, 22 March 2011 (UTC)