Talk:De Havilland DH 108/Archive 1

Archive 1

Sound Barrier Dispute

There seems to be a dispute about the F86 beating the DH108 through the sound barrier. I am well aware of the disputed status of the 1947 "sound barrier" flights, and this is unlikely to be resolved at any point, however there was an official flight through the sound barrier on April 26th 1948. This clearly beats the first recorded flight through the sound barrier of the DH108 on 9th September 1948 by over 4 months.EddieWalters 23:04, 18 August 2007 (UTC)

Not only was there no official record which has to be verified by independent witnesses and instrumented data, but there is a wealth of evidence that North American test pilot George Welch did not break the record at all. In the spring of 1944, Welch joined North American Aviation as a test pilot for the P-51 Mustang and later, the FJ Fury and F-86 Sabre. As the chief test pilot, he carried out test flights from September, 1947 at the Muroc test facility (now Edwards AFB, California), the same base at which the Bell X-1 was being developed. North American was instructed by Secretary of the Air Force Stuart Symington that they were not, under any circumstances, to break the sound barrier before the X-1 achieved this milestone. However, Welch disregarded this order, and during a test flight on October 1, 1947 he entered a steep dive from 35,000 ft. During the dive, Welch observed symptoms compatible with Mach jump, and according to some, a sonic boom was heard at the base. However, due to problems with the landing gear, further full-speed flights were delayed. On October 14, the same day that Yeager was to attempt supersonic flight, Welch reputedly performed a second supersonic dive. This time he started from 37,000 ft, and executed a full-power 4g pullout, greatly increasing the power of his apparent sonic boom. Yeager broke the sound barrier approximately 30 minutes later. Welch had no verification, no instrumentation, no record. FWIW Bzuk 04:23, 19 August 2007 (UTC).

BTW, dives are not considered for speed records, only straight-line, level speeds. FWIW Bzuk 06:38, 19 August 2007 (UTC).

Bzuk - don't accuse me of rewriting history without reading the sources I provided. I never claimed that Welch's reported flights before Yeager were the flights that . However, it is officially recorded and acknowledged by the USAF that in April 1948, Welch passed through the sound barrier on an officially verified flight. This version of events is referred to on the F86 Sabre page on Wikipedia, on the link I posted as a reference - http://www.aerospaceweb.org/question/history/q0113.shtml - and numerous other websites (including the National Air and Space Museum http://www.nasm.si.edu/research/aero/aircraft/NAF-86.htm). I believe these are credible sources. I am by no means trying to take anything away from what de Havilland achieved, but I am not comfortable with the page in its current state. You claim that "dives are not considered for speed records". I quote the exact wording of the DH108 article "Then, on 9 September 1948, it exceeded the speed of sound in a shallow dive from 12,195 m (40,000) ft to 9,145 m (30,000) ft.". In reference to the XP86 record (as it was still referred to as the XP86 in April 1948) the National Air and Space Museum website states "In April 1948, the XP-86 exceeded Mach 1 (the speed of sound) in a shallow dive."

I don't know what kind of source you need to see to convince you, but there are MANY pages available at: http://www.google.com/search?q=XP-86+Sound+Barrier+April+1948. I cannot find any credible websites that claim that the DH108 was the first jet aircraft to break the sound barrier.

Clearly looking at the history of this page, this issue has been raised before. We need to come to a consensus answer and resolve the issue.EddieWalters 14:30, 19 August 2007 (UTC)

Eddie, you are right, I jumped to conclusions that you were claiming the earlier unverified flights were being recognized. It was a verified flight that took place although not an official record. My apologies. I have corrected the note in the article with a reference source cited. Too many late nights on the computer, too many fights with vandals, coming across someone I had never seen editing before, all these are feeble excuses. You did a sterling job in explaining the issue and I commend you. FWIW Bzuk 14:49, 19 August 2007 (UTC).

John Derry never claimed to have exceeded Mach 1 - it was the Press and similar who tried to claim. Derry explained to Eric "Winkle" Brown prior to Brown flying the aircraft that whilst diving VW120 at high speed, having finished his observations, he let go of the stick in order to turn the recording equipment off and the aircraft 'ran away' and he was unable to prevent it gaining speed. He noticed the Machmeter jump momentarily over 1.0 before regaining control. At the same time several people on the ground reported hearing a loud bang. Derry never made anything of it because the recording equipment had been off at the time, so it couldn't be substantiated.

BTW, Brown himself got the 108 VW120 up to Mach 0.985 without too much trouble but that was diving from 45,000ft, the thing that appears to have got de Havilland killed was the low altitude he was flying at - below 10,000ft - where the air was thicker and the extremely violent oscillations occurred. According to Brown, this behaviour started to make itself felt the lower the altitude one started the dive from, becoming more violent as the starting altitude of the dive was decreased, and he experienced it himself at one particular region, at 4,000ft and at Mach 0.88.

When the accident that killed him occurred, de Havilland was flying at 7,000ft and doing Mach 0.875.—Preceding unsigned comment added by 86.112.64.88 (talk) 11:26, 19 March 2011 (UTC)

Wing made of Wood??

In carrying out research on the aircraft, I have been supplied some pictures of the wing in assembly jigs. They are made of metal, using a mixture of modified Vampire parts, and bespoke parts. However, I dont have any verifiable references that will confirm this. I have changed the wording in the main article accordingly, and am open to suggestions on how we might reference this? Brucewgordon (talk) 13:52, 6 December 2007 (UTC)

Fair use rationale for Image:DH 108 Swallow TG283.jpg

Image:DH 108 Swallow TG283.jpg is being used on this article. I notice the image page specifies that the image is being used under fair use but there is no explanation or rationale as to why its use in this Wikipedia article constitutes fair use. In addition to the boilerplate fair use template, you must also write out on the image description page a specific explanation or rationale for why using this image in each article is consistent with fair use.

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BetacommandBot (talk) 05:26, 2 January 2008 (UTC)

re: Eric Brown and George Welch

there seems to be no rteference to Eric Brown's follow-up flight after Geoffrey DeHavilland's fatal accident http://en.wikipedia.org/wiki/Eric_Brown_(pilot) includes this, if it is of interest. In http://www.space.co.uk/DataBank/VideoGallery/VideoPlayer/tabid/384/VideoId/33/Test-Pilot-Discussion.aspx (which also discusses the DH108) Eric Brown responds to the issue of whether George Welch beat Chuck Yaeger to mach 1. (the conclusion as I understand it is that he most likely would have, but in a dive, and it would have been kept secret for publicity reasons)

Hope I got this edit right, and that it's helpful.

85.196.101.178 (talk) 18:23, 26 June 2010 (UTC)

The BBC podcast detailing the record of Eric Brown BBC:Iplayer (2 October 2019). "Britain's Greatest Pilot:The Extraordinary Story of Captain Winkle Brown" (Podcast). Event occurs at 46 mins. Retrieved 2 October 2019. details the Farnborough enquiry and Brown's terrifying experience of repeating his fatal manoeuvre, losing control during a 3hz oscillation between =4 & -3 g. Recognising from his previous research, the risk of blacking out after 10 seconds, he regained control after 7 seconds by pulling back the throttle and joystick. There seems to have been a change of rules disqualifying podcasts as a source once they are no longer available. I'm adding this to help other editors and in the hop that this magnificent program becomes available albeit perhaps on YouTube. Regards JRPG (talk) 11:50, 2 October 2019 (UTC)

lowercase template

It is an abuse of the {{lowercase}} template to use it for names like "de", "von", etc. These names are uppercase when they start a sentence, so the article name should be uppercase. The correct use of the template (which is fairly rare) is for things that are never capitalized, that would actually be incorrect if capitalized even at the start of a sentence (examples are eBay, iPhone, e (mathematical constant)). --Trovatore (talk) 17:40, 24 August 2012 (UTC)