Talk:North American X-15/Archive 1

Mach # on first flight
There's an error of fact in the last change, about the X-15's first flight making Scott Crossfield the first to go supersonic in a glider. The first flight only had a top speed of Mach 0.79.

However, the Southern California Soaring Society (might have been Association instead of Society) did award a trophy to Crossfield for the fastest glide to a landing from 38,000 feet on that flight. The trophy was a nicely finished and mounted streamlined brick.

Perhaps the author of this note would like to update it.

Another possible notation would be that this was one of only two X-15 flights whose top speed was subsonic. The other was an emergency landing by Forrest Petersen when the engine didn't light -- even then he got to Mach 0.97, almost supersonic in a pure glide. On all other flights the X-15 operated as a motorglider, so it's still fair to say that it was the fastest glider on record until the Space Shuttle's first reentry.

Actually this note is partly a familiarization exercise, I just registered and am checking out details in Wikipedia. That explains some of the text oddities in this note. --Paul Raveling 07:38, 12 January 2006 (UTC)

Measurement Units
I only see the speed and altitude listed in Metric in the Record Flights and Pilots sections. I know that most of the world uses the Metric system, but since this is an American aircraft, it stands to reason that the performance is listed in our units, too. TwinTurboZ 05:07, 8 February 2007 (UTC)

Adding Links
After seeing pages from the Aviation Trivia web site linked to from Wikipedia articles, it seemed appropriate to ad a link to pages that have much more comprehensive statistics regarding the aircraft and a wav file of how it sounds. That was the reasoning for the single link I added to the one page. The other links were added by others. The link already on the page: Another link to an unofficial X-15 web site appears to be inoperative. Perhaps it should be removed. --Crvarvaro 08:03, 5 March 2007 (UTC)crvarvaro

Other incedents of X-15
Article should include the following summaries and links

ID# 56-6671 (AC2?) 10/17/1959 - On Scott Crossfields third flight, one of the two XLR-11 engines exploded forcing an emergency landing that broke the aircrafts back just behind the cockpit. Ref http://en.wikipedia.org/wiki/Scott_Crossfield

ID# 56-6672 (AC3?) 6/8/1960 - (Scott Crossfield) While testing the XLR-99 in a ground tether test, the engine exploded blowing the nose section approximately 40 feet from where the Aircraft was tethered. The pilot was uninjured. The aircraft was repaired (as evidenced by subsequent flights of same AC) Ref http://en.wikipedia.org/wiki/Scott_Crossfield   http://en.wikipedia.org/wiki/List_of_X-15_flights

Perhaps a section of incendents and accidents should be made that includes these items along with the accident that resulted in the death of Adams. —Preceding unsigned comment added by 198.31.184.166 (talk) 20:01, 4 October 2007 (UTC)

Pilots
The table at bottom says that Joe Walker flew the X-15 as a USAF pilot. That is incorrect. He was the lead test pilot on the project for NASA. —Preceding unsigned comment added by Rocksci (talk • contribs) 05:06, 14 November 2007 (UTC)
 * Could it be that he was an Air Force pilot attached to NASA? This was common in the early days of the space program.
 * Have a reference for that claim? If so, BE BOLD!!! and add it. — BQZip01 —  talk 09:52, 14 November 2007 (UTC)

Service ceiling?
Where did this stat come from? I understand service ceiling to be the highest altitude an aircraft can operate because there's too little air either to generate lift/use flight controls or initiate combustion in a conventional engine. The X-15 having both a liquid fueled rocket engine and reaction control system doesn't need any air to operate being limited only by fuel. (I've always wondered how high it could've gone had they used 66671 with its drop tanks to go for maximum altitude or if it could've attained a low sub orbital trajectory had they done such an experiment near the equator.)

If it's just the highest any X-15 flew we should remove it, however if this is a NASA/North American/USAF figure we should cite it. Anynobody 08:15, 19 February 2008 (UTC)

Actually, the service ceiling is the altitude beyond which an aircraft is no longer able to maintain a rate of climb of 100 feet/min. I'm not sure the term would even apply to the X-15. Nibios (talk) 15:29, 5 May 2008 (UTC)

Nomenclature
I question this use of -1 and -3 in conjunction with the X-15. One and three were X-15As. Only the second one was modified into a dash-2 variant. Adding -1 and -3 to the other two may indicate the order they were serialled in, but is misleading insofar as the actual designation is concerned. Mark Sublette (talk) 22:31, 9 June 2008 (UTC)Mark SubletteMark Sublette (talk) 22:31, 9 June 2008 (UTC)

I agree that the nomenclature used is confusing. The "re-named X-15A-2" after reconstruction/repair should indicate what its previous designation was. —Preceding unsigned comment added by 24.40.148.223 (talk) 22:12, 26 January 2009 (UTC)

Comparable Aircraft
Does anyone think that SpaceShipOne should be under "Comparable Aircraft?" And what about the X-20? It was designed to be launched on a Titan, and was designed for orbital operation. Does this really count as a comparable aircraft? Just my 2¢ --68.151.44.253 (talk) 04:02, 29 June 2008 (UTC)
 * I agree, and I added SpaceShipOne (but before I read this). As far as I am concerned, the SS1 program had all the same goals as the X-15 program and the vehicles are almost as similar as one could imagine given the different time periods they are made in and the differing construction materials.Bollinger (talk) 05:07, 7 May 2009 (UTC)


 * Neither one are similar/comparable, and I've removed them, per WP:AIR/PC guidelines on this template. SS1 is certainly not on the same era. - BillCJ (talk) 05:49, 7 May 2009 (UTC)
 * In your comment, you say SS1 is not comparable in role or era. How is it not comparable in role? Both were efforts to reach the edge of space as a stepping stone to make further spacecraft. Bollinger (talk) 07:43, 7 May 2009 (UTC)

fuel?
it was hydrogen peroxide and hydrazine or something similar? —Preceding unsigned comment added by Ericg33 (talk • contribs) 00:18, 18 July 2009 (UTC)

Spaceplane or airplane?
There is no doubt in my mind that the X-15 is actually a spaceplane, it doesn't matter what everyone else calls it if they are all wrong.

Assume the premise: the SpaceShipOne is a pure spaceplane -- which seems to be the current consensus (see the article on that subject). Given that premise, then how can it possibly be argued the X-15 is not the same kind? Why should the X-15 get the title aircraft/spaceplane and not the 'pure' spaceplane title? —Preceding unsigned comment added by Posix memalign (talk • contribs) 05:25, 6 May 2009 (UTC)
 * The X-15 was a research aircraft and many of its flights did not explore the upper range of altitude. NASA describes it as a hypersonic research vehicle but it did achieve suborbital heights to qualify as a spaceplane, which is the modern or current nomenclature for the type of aircraft. FWiW Bzuk (talk) 07:06, 6 May 2009 (UTC).
 * Do you suggest the craft be described as "hypersonic research vehicle"? I find that dismissive in the current context -- hypersonic describes the sheer speed to some note, while "research vehicle" describes the intent -- the said terms do not entail anything about the height it can reach. The context is if it should be called an aircraft, spaceplane or both. The term "hypersonic research aircraft" is used later in the article already though.
 * In short, my position is that I don't see how the SpaceShipOne is any more a spaceplane than the X-15, the X-15 may not have reached beyond 100 km on most of its trips, but as far as I know that was not due to lack of ability, the SpaceShipOne did not reach beyond 100 km on most of its attempts either, why should the two crafts be described with different terms? —Preceding unsigned comment added by Posix memalign(talk contribs) 16:05, 6 May 2009 (UTC)
 * The X-15 series is described as both a rocket-powered aircraft and a spaceplane. FWiW, the type of aircraft is what is being described. Bzuk (talk) 22:01, 6 May 2009 (UTC).

I know NASA didn't call it a spaceplane, but the term didn't exist at the time. Which isn't odd, as the X-15 was the first one. By modern terminology, it's a spaceplane, even if it didn't go to space every time. If you look at the spaceplane page, it's of the rocket-powered subclass (the only kind that actually exists so far). It was designed to go to space and it did. It is vehicle that flies to space and it is aerodynamically maneuverable when in the atmosphere. That's a spaceplane. If you go to the spaceplane page you can see that spaceplanes can also act as aircraft. Are we supposed to vote or something now? Bollinger (talk) 03:15, 7 May 2009 (UTC)
 * NASA doesn't call it a spaceplane now. It is established that it is "rocket-powered", an "aircraft" and a "spaceplane"; that's what is in the article. FWiW Bzuk (talk) 03:18, 7 May 2009 (UTC).
 * Because official pages at NASA don't call the X-15 a spaceplane doesn't mean it isn't -- since the term did not exist at the time it is clear it is called a "rocket-powered aircraft" merely for historical reasons, which is very often the case with terminology in general.
 * The bottom line is this: Either the X-15 is an "aircraft/spaceplane" AND SpaceShipOne is an "aircraft/spaceplane", or X-15 is a "spaceplane" AND the SpaceShipOne is a "spaceplane" -- the main issue I'm having here is that we can't designate a different class to the SpaceShipOne than the X-15, they have to be the same class. I vote to call the X-15 a spaceplane, it isn't even designed to have functionality to take off with its own systems, it is an aircraft designed to be launched from a B-52 and reach past the edge of space, and do experimental research while doing so. It is an experimental spaceplane. Posix memalign (talk) 03:33, 7 May 2009 (UTC)
 * It is described as both a rocket-powered aircraft AND a spaceplane, isn't that enough? FWiW, if a verifiable and authoritative source can be provided then the lede and infobox can reflect that type designation.Bzuk (talk) 03:44, 7 May 2009 (UTC).
 * Technically, the X-15 could actually operate from a ground launch, although the aerial drop was optimum for achieving highest velocity and altitude flights. The predecessors to the X-15, the X-1, X-2 and Skyrocket aircraft could equally operate from a ground or air launch with a notable flight by Chuck Yeager in the X-1 establishing that the research craft was an "aircraft". The marginal fuel load was one of the determining factors in not continuing with ground launches. FWiW Bzuk (talk) 03:59, 7 May 2009 (UTC).
 * A (rocket-powered) spaceplane functions as a rocket-powered aircraft when it is in the atmosphere. So on a flight where it doesn't leave the atmosphere, it operates as rocket-powered aircraft exclusively. But that doesn't mean it's not a spaceplace. The spaceplane entry clearly explains that what a spaceplane does also encompasses everything a rocket-powered aircraft could do. Frankly, the first paragraph of spaceplane describes the X-15 (or SSOne) perfectly. I don't get the controversy. As to the idea of getting excited that NASA doesn't call the X-15 a spaceplane, laptop computer manufacturers all call them "notebooks", but does that mean we can't call them laptops? Wikipedia seems to think that's okay.Bollinger (talk) 05:03, 7 May 2009 (UTC)

(Unindent) I have yet to see the reliable sources attesting that the X-15 is considered a spaceplane, so have removed such claims from the article. A jeep or a 4-wheeler may run on the beach and get wet, but that doesn't make them amphibious vehicles. The X-15 explored the edge of space, but it wasn't designed as a spacecraft the way spaceplanes are. - BillCJ (talk) 05:54, 7 May 2009 (UTC)
 * Wow, I guess I see what discussion is really good for now. This is a clearly an owned article. Message received. At least I don't have to worry about coming up with arguments anymore. Bollinger (talk) 07:46, 7 May 2009 (UTC)
 * As indicated earlier, the X-15 is both a rocket-powered aircraft (standard descriptor) AND a spaceplane (modern convention). For a verifiable and authoritative source, I will try to establish the use of the new term. FWiW, this discussion is not entirely moot, but as this discussion "string" had been developing, like the earlier comment indicated, an attempt to locate a bonafide source has proved elusive, regardless of the WP:DUCK allusions. My attempts to reconcile two varying opinions was the compromise I proposed. One of the problems is that the descriptor "spaceplane" is not yet in common usage. I have seen a number of variants in spelling with "space plane" actually being the more common spelling derivation. If the term is merely a writing convention or a colloquialism, then that complicates the arguments around whether the X-15 can be truly be considered a "spacecraft" (a term which incidentally does have a more traceable origin and credentials to back it up). Bzuk (talk) 09:20, 7 May 2009 (UTC).


 * Both the NASA and Boeing sites clearly call it an aircraft/airplane. While it did cross into the edge of space, it only did so twice (IIRC) out of about 200 flights. Btw, its highest altitude was about 67 miles; some researchers in Calgary announced this year that they had "found" the true edge of space (at 87 miles, IIRC). Interesting. - BillCJ (talk) 17:59, 7 May 2009 (UTC)
 * So what if NASA and Boeing states that it is an aircraft/airplane? Let them call it whatever they want! Terminology is often used incorrectly, e.g. take a look at computer products, they consistently use the ambiguous decimal prefix units when they actually mean binary prefix, it is WRONG, but they still do it. Merely because Intel and IBM states it in this manner does it make it law? Even if almost everyone, including major hardware producers state several key terminology terms wrong it doesn't make it right, it is still wrong! In almost the exact same manner, but on a smaller scale, it is completely wrong to describe the X-15 solely as an "aircraft" -- to the uninformed reader it is fallacious and deceptive, aircraft does not in any way necessarily imply spacecraft capability, it only implies what is commonly associated with a standard aircraft.
 * I reiterate, the X-15 is a spaceplane: The X-15 has spacecraft capability, it can reach > 100 km, it has attitude control in the vacuum of space, it has life support for this altitude, it can safely re-enter the atmosphere.
 * "Spaceplane" definition: "A spaceplane is a rocket-powered aircraft designed to pass the edge of space."
 * X-15 meets with no doubt "rocket-powered aircraft designed to pass the edge of space", does it not? Yes, it does, it met both USAF spaceflight criteria and the international FAI definition of a spaceflight -- this is even stated in the article itself!
 * Ergo, the X-15 is a spaceplane! Q.E.D. Posix memalign (talk) 04:32, 8 July 2009 (UTC)
 * The X-15 was not expressly designed as a spaceplane although it had the ability to reach "outer space"? or at least marginally reach a predefined altitude that qualified its pilots as astronauts. The X-15 was designed to explore high speed and the thermal thicket as well as reach altitudes in excess of other aircraft. From the "string" above, you do not have consensus for a change to a different interpretation. Since NASA and other authoritative bodies describes the X-15 as a rocket-powered experimental aircraft, that is the best descriptor that can be used. FWiW, BADH is now involved,Bzuk (talk) 04:42, 8 July 2009 (UTC).
 * I'm sorry but I find your logic to be flawed, here is why: All design per se does not necessarily have to be stated explicitly, it can be an implicit consequence of other stated goals and still be included in the design; e.g. if we are to build a very fast commercial airliner, we state our goals in what we wish, but do not state explicitly that it is to be supersonic -- if this same aircraft happens to be supersonic, is it not a supersonic aircraft? I have no idea what BADH means. Posix memalign (talk) 04:50, 8 July 2009 (UTC)
 * Beating a dead horse, but keep pounding away (LOL- laughing out loud- signifying a joke, not laughing at you). FWiW (for what it's worth), all you needed to do is what I had suggested in the first place, find an authoritative and verifiable source, yourself excluded, of course, and proceed to make an valid case for a change. Bzuk (talk) 04:58, 8 July 2009 (UTC).
 * I tried to explain why this is difficult with my analogy with decimal prefix and binary prefix -- see if you can find any authoritative source (from any major manufacturer) that states the actual amount of MegaBytes in a modern memory DIMM -- i.e. see if you can find the term "GiB" instead of "GB". While the analogy is not perfect it illustrates my point. Or see if you can find a HDD manufacturer who states the accurate amount of GiB in their HDD. How can I find an authoritative source that states the correct term when every current available source is incorrect?
 * Allow me to try a different approach. Why do you believe the SpaceShipOne should earn the title "spaceplane"? Merely because it stated explicitly in the design goals to reach the edge of space?
 * Imagine we are in the future, several common aircraft can exceed the edge of space merely as a natural result of the high performance envelope -- even though reaching past the edge of space was never stated in the design specification; should we call all of these aircraft merely aircraft as well, while the sole determining factor for spaceplane is in the design specification?
 * Only two flights of the X-15 made it > 100 km? How does that make any sense as an argument? The important question to ask is if the X-15 was pushed past its specification limits to do so, if the pilot decides NOT to go past the edge of space on purpose, how does that describe anything at all about the X-15 itself? Posix memalign (talk) 17:07, 8 July 2009 (UTC)


 * Interestingly enough, a user has tried to claim that the SR-71 is a spaceplane at Talk:Spaceplane. Btw (By the way) BillZ, are the F-86 and the like considered a supersonic aircraft because when can do so only in a dive? I think they usually use the term transonic, but I'm not certain. And I don't see a problem with just stating the facts here: The X-15 is an aircraft that crossed the line of space twice out of over 200 flights. That is what the reliable sources say - leave it to the reader to decide if that makes it a spaceplane or not. - BillCJ (talk) 05:29, 8 July 2009 (UTC)
 * The X-15 marginally could be considered a "spaceplane" but as indicated previously, to make a claim such as this, attributable sources must be used. Aircraft such as the F-86 and even the CF-100 could achieve supersonic speeds, but only in dives not in "level" speeds, so "transonic" is correct; while the SR-71 may have had the capability like the X-15 to reach the nether regions of space, it too cannot be considered legitimately a "spaceplane." Again, anyone can prove their case with an authority that backs up the assertion. FWiW Bzuk (talk) 05:49, 8 July 2009 (UTC).


 * Btw, BillZ, the "correct" term on WP is space fixed-wing aircraft. A "spaceplane" is a carpenter's tool on the space shuttle or the International Space Station. Let's be consistant, OK? ;) BilCat (talk) 06:06, 8 July 2009 (UTC)
 * Check back on the "string" above and you will find that the terminology is one of the issues as there is no acceptance of the term, is it a spacecraft? spaceplane, space plane (spelling variations here)? space fixed-wing aircraft? fixed-wing space aircraft? reusable space vehicle? As to your "correct" term, show me the ref?! Bzuk (talk) 07:35, 8 July 2009 (UTC).


 * Are you daring to question my infalibility? Again? I said it, that makes it so! Anyway, whatever term is used, it can't use "plane" in the word - that's not allowed in WP when referring to aircraft, even hybrid spacecraft. ;) Does it make any sense? Absolutely not, but that hasn't stopped WPAIR from imposing the "we can't use 'airplane' or 'aeorplane' rule" because they didn;t want to stand up to the language zealots from either side of the Atlantic, or the alternative most of those editors would accept, the dreaded "plane"! - BilCat (talk) 07:49, 8 July 2009 (UTC)


 * And "airplane" is good enough for britannica.com! - BilCat (talk) 07:56, 8 July 2009 (UTC)
 * ...and a plane is? a woodworking tool?! while aeroplane and the uniquely American derivation is so yesterday while the gaudy and illustrious AIRCRAFT rules triumphant. Please don't throw up this canard as it smacks of more than WP:DUCK. Prithee, thouest might further consider aerodrome, aero flivvers or the like... FWiW, and infallibility? how can I not trust an authority who has cleverly devised alternate spelling conventions for: aeorplane, consistant, didn;t and infalibility?!! Bzuk LOL (talk) 11:24, 8 July 2009 (UTC).


 * As a highly-experienced mild-mannered libarian, I'm sure you're fully aware that plane is also a term used in Geometry, and that others are probably aware of it too. If we can have two definitions of plane, I have no problem with recognizing one more that is already used. ANd sotp pikcign no my tpyinng! I cna speel, O jsut cant' tpye! :( - BilCat (talk) 17:15, 8 July 2009 (UTC)
 * We have digressed rather far from the topic, haven't we? Nevertheless, but my final "sally forth" as the last comment brings to mind the old chestnut of putting enough monkeys on typewriters, and given enough time, there is a likelihood that the works of the bard would be produced. Perhaps if you are having difficulty in typing, enlisting one of the monkeys may be a recourse... LOL Bzuk (talk) 22:32, 8 July 2009 (UTC).


 * My two cents here... The X-15 may be able to reach the edge o space, though that's recently been debated...  But by the same token, it can also be crashed into another vehicle, causing destruction of said vehicle.  That doesn't make the X-15 an air-to-air missile, it just means that one of its capabilities exceeds its design.  Side note: "transonic" is not that it can dive to reach supersonic speeds...  There is the subsonic range (slower than around mach .85, as memory serves), transsonic (mach .85 to 1.2, again as memory serves), and supersonic (faster than mach 1.2).  The reason for this is the differing aerodynamics associated with each of those speed ranges.  -Tim (this isn't my home computer, so not wanting my IP to show up)  —Preceding unsigned comment added by 130.76.96.21 (talk) 19:18, 20 August 2010 (UTC)

"reign supreme among rocket-powered aircraft until the second spaceflight of Space Ship One" -- What? Elvis reigned supreme. Some objectivity please? — Preceding unsigned comment added by Expetcompsci (talk • contribs) 08:21, 19 June 2011 (UTC)

Wedge tail
I've puzzled over why the X-15's vertical tail surfaces had a wedge shape, rather than a full airfoil. It seems to me that a wedge, with its flat rear, would have much higher drag. Hellbus (talk) 23:29, 12 September 2009 (UTC)
 * not necessarily at supersonic, and notice stabilators for same reason Accotink2  talk 20:10, 28 July 2010 (UTC)

Apparently it could produce a lot drag, but was needed for stability at hypersonic speeds. Check about half-way through chapter 3 of SP-60 for more about this. Fotaun (talk) 15:28, 4 October 2011 (UTC)

Pilot in the cockpit at takeoff?
or did they have a way to transfer from the B52 in flight? Midgley (talk) 01:04, 30 June 2011 (UTC)
 * In the cockpit: Says here they got into the X-15 about 45 minutes before the B-52 took off, and stayed there till they landed. Fotaun (talk) 16:02, 4 October 2011 (UTC)

== The first photo on the page shows an X-15 aircraft with white frosted panels, has completely inaccurate descriptions. The number of the flight (thus date of launch and other details) can only be assigned as one of these: 34,35,36,37,38,40,41,43,53,55,60,63,66,68, or 69 (out of 199 total flights among the 3 airframes in the program), not flight number 2, 17 Sept 1959. The author failed to confirm which flight was actually captured in that photo. A quick consultation of the book titled Hypersonic, with its excellent flight summary, makes clear that the aircraft cannot be representative of its sate in such an early flight. Airframe number 2 (66671) had the nose boom and dual XLR11 engines on the date 17 Sep 59. The aircraft as of the photo date had the ball nose, and single XLR99 engine. I ruled out flight 45 since the entire canopy was painted in white heat sensitive paint. Flight 70 is ruled out since the leading edge of the vertical fin lacks the protruding sharp leading edge, and still has the ventral fin (all flights by this point lacked this fin, not to be confused with the small residual ventral fin). The problem does not end with the description in the main page. Click the photo and the page you get is even further off the mark. Please fix the information regarding this photo! — Preceding unsigned comment added by 67.189.79.132 (talk) 06:49, 15 April 2012 (UTC)

Untitled
There is a problem with intrapage consistency. At the top of the page, the limit of 100km for "space" is attributed to the FAI whereas at the bottom of the page it is attributed to the FAA. Someone needs to sort this out? — Preceding unsigned comment added by 12.220.20.226 (talk) 03:04, 28 April 2004 (UTC)

Also, the top of the page say 13 flights have made it over 50 miles, but the bottom says 12. Jwolfe 08:11, 3 Jul 2004 (UTC) (the above comment is not mine, just this one).


 * Also, "Performance Characteristics : Max Speed" figures don't jive with the "Fastest Flights" chart. Sadsaque (talk) 14:21, 22 August 2012 (UTC)

German Engineering
It's funny, no disappointing, that you can't find something about the German roots of that plane, of the whole space program in fact. Just look up the articles about "Aggregate (rocket family)", "V-2 rocket" or "Aggregat 9" a concept (not in English) and the use of the v2 rockets... — Preceding unsigned comment added by 193.171.244.23 (talk) 13:48, 8 February 2013 (UTC)


 * To say that the X-15 is "based" on german technology simply because it looks like a V2 (i.e. long and pointy) is, to put it mildly, a very simplistic way at looking at the two aircraft and only your opinion. The X-15 has to deal with the same physics/aeronautical/fluid dynamics constraints so you would of course assume that they'd look somewhat the same. Nothing more. Ckruschke (talk) 20:15, 8 February 2013 (UTC)Ckruschke


 * I NEVER said it looks similar, i said you have to look up some articles! Just read the Articles, even the german one, understand them AND explain why in the English one there is hardly nothing written about the history and the people working at that plane. Maybe because some don't want to read that? — Preceding unsigned comment added by 193.171.244.8 (talk) 15:22, 13 February 2013 (UTC)


 * It's actually because there was very little real influence of German design concepts in American aeronautics, beyond some data confirming independently developed theories. A lot of sound and fury is made about Operation Paperclip and results therof, but when you strip away the myths and propaganda a very different picture emerges. - The Bushranger One ping only 15:25, 13 February 2013 (UTC)


 * Walter Dornberger is mentioned in the first sentence of the article's main section as being the author of a "concept study" on which the X-15 is based, but without seeing the source, I can't know the extent of the study, or how much of it contributed to the X-15's actual design, especially as Dornberger worked for Bell Aircraft at the time. What is in the German article appears (based on Google translation of the article) to be merely speculation that there is a direct connection to the WW2 rocket designs without any real proof given. It is true that much of the US space program and other aeronautical programs benefitted much from the participation of German engineers, but so did the Soviet programs, to an even larger extent. - BilCat (talk) 17:52, 13 February 2013 (UTC)


 * The "German roots" of a plane that was designed by North American Aviation in California? Seriously! Perhaps you would care to credit the Germans with North American's B-70 aircraft as well. They probably invented the Lockheed F-104 too, and, oh yes, the SR-71. The Germans must have invented everything. Did we steal the nuclear bomb from them as well. How about radar? Even von Braun said they just shaped the V-2 like an artillery shell because that was a shape everyone already knew worked at supersonic speeds. But that's only fair, because the Germans must have invented artillery too. I grow really tired of these "everything out of Germany theories". They are as tiresome as conspiracy theories and UFO stories. Goddard didn't invent liquid propellant rockets but von Braun did. And on and on. Does anyone even remember that Reaction Motors, Inc. and Aerojet were producing liquid propellant rocket engines all during WWII, or that Rocketdyne tube-bundle engines became the industry standard for liquid propellant rocket engines because they did NOT follow the German V-2 engine design practice of using heavy double-walled construction and hydrogen peroxide driven turbopumps? And how about Atlas, a missile that weighed 10 times as much as a V-2 but had a lower burnout weight. How could that be if Atlas wasn't German? I appreciate German engineering as much as the next professional engineer, but I'm not obsessed with it. Magneticlifeform (talk) 06:19, 10 March 2013 (UTC)

Fastest manned Aircraft?
I somehow doubt that the X-15 currently holds the world record for the fastest speed ever reached by a manned aircraft as the Space Shuttle, The Soyuz capsule and even the Mercury/Redstone capsule travelled well beyond what the X-15 could acheive. Doggie015 (talk) 05:35, 5 June 2009 (UTC)


 * You are obviously right, but the vehicles you describe are not recognized to be in the same class as the X-15 by Wikipedia -- the X-15 is, for some absurd historical (or whatever) reason, recognized by Wikipedia as only an aircraft, whereas e.g. the Space Shuttle is a spacecraft that contains a winged spaceplane. Given the premise the X-15 is merely an aircraft it is the fastest manned aircraft as of yet -- if we ignore the fact that the premise is wrong.Posix memalign (talk) 04:38, 8 July 2009 (UTC)


 * The record should be an official one recognized by an aviation organization, like the Fédération Aéronautique Internationale. It should be easy to find out, and that would be from a reliable source. - BillCJ/BilCat (talk) BilCat (talk) 06:05, 8 July 2009 (UTC)


 * I've updated the article to say that it was Rocket powered, to try and clear things up a bit.88.96.109.201 (talk) 13:12, 8 April 2010 (UTC)


 * I agree. How does the X-15 fit the definition of 'aircraft' while the space shuttle does not?50.125.138.24 (talk) 05:18, 7 May 2013 (UTC)
 * Because the X-15 is classified as an aircraft by the FAI, while the Space Shuttle is not, likely as orbital craft are not considered aircraft. - The Bushranger One ping only 06:56, 7 May 2013 (UTC)

Engines and fuel
-Update. I use WikiTweaks, a Firefox extension, & QuickWiki is one of the features. I turned it off, & then back on. This (eventually, when I woke up the next day) showed me the problem. It's now off. Dick Holman. User:Archolman 01:10, 27 July 2010 (UTC)

Re-write to remove the craft description, as this is detailed in the previous section, & later in the article. Dick Holman. User:Archolman 01:38, 27 July 2010 (UTC)


 * Dick, please stop changing the "Engines and fuel" section, and try to work out a solution here witht he other editors first. I understand you're new, but there are several factors at work here that need to be addressed.


 * First, you seem to be removing, without comment, another editor's contesting of the X-15 being the first aircraft with a throttleable rocket engine. Whichever claim is true needs to be backed up by a Reliable source. I've added a citation needed tag for the time being. Please present your sources here first, and we'll try to work out the differences.


 * Second, the phrase "could be throttled, like an airplane engine," is vague and probably inaccurate, and really doesn't need to be used at all. There are many types of "airplane" engines, and some are not throttleable. Futher, there have been other rocket-powered airplanes such as the X-1, which presumably weren't trhottleable, and thus that invalidates the vague claim that airplne engines are trottleable!


 * Third, and this one is unique to Wikipedia, is that the use of "airplane", "aeroplane", and "plane" are deprecated in favor of the terms "fixed-wing aircraft" when being specific, and "aircraft" when being general. While a very stupid rule, it's a compromise that was reached several years ago because some editors on both sides of the Atlantic refused to accept the ussage of the other side's term. - BilCat (talk) 04:52, 27 July 2010 (UTC)


 * The X-15 use the same principle dual flow Walter Turbo pump driven by a Walter steam generator used for the V2 and Me 163B! below in this picture can you see the Walter turbo pump. The HWK engine is well known trottleable and restartable. I suggest "Peene Münde West from Botho Stüwe" and this . Page 5 The Walter engine as flown in the He 112 was the first to incorporate controllable thrust with the utilisation of a steam driven turbopump for the T Substance. The He 112 used the cold Walter system and the Me 163 the hot Walter system. Page 12 Me 163B.--HDP (talk) 18:02, 28 July 2010 (UTC)


 * Then is the term throttleable for the XLR 99 questionable the thrust is only adjustable between 50% and 100%. The HWK 105-509 thrust was adjustable between 10% and 100%.--HDP (talk) 18:32, 28 July 2010 (UTC)

The main engine of the X-15 is throttleable as shown in this historical documentary (and they speak about it few times across the documentary) 112.201.208.199 (talk) 00:55, 19 June 2016 (UTC)

Re-entry
How did it re-enter the atmosphere? It had no heat shield, did it? --212.186.14.29 (talk) 12:02, 25 October 2016 (UTC)
 * It didn't need a heatshield; it was not a ballistic spacecraft which descended through the atmosphere at high speeds like the Mercury capsule, but rather an airplane. Airplanes don't need heat shields because they don't descend through the atmosphere at high speed; the wing's lift slows their rate of descent. This is one of the problems of Wikipedia stressing the "space flight" aspect of this vehicle. I maintain it was a high speed, high altitude aircraft and not a "spacecraft", despite the fact it had non-air-breathing engines and thus capable of brief spaceflight (defined as above the substantial atmosphere.) JustinTime55 (talk) 14:15, 25 October 2016 (UTC)


 * Well, more than 7.000 km/h is according to me a "high speed". Virgin Galactic's SpaceShipOne and Two travel at a speed of "only" 3.000 km/h through the atmosphere and already therefore they need the so-called feathering system for re-entry. X-15 must have had a similar system. --212.186.14.29 (talk) 14:32, 25 October 2016 (UTC)


 * My understanding is that the SpaceShipOne's feathering system is about providing both high drag and flight stability. The X-15 may simply have not needed these considerations. — Huntster (t @ c) 18:28, 25 October 2016 (UTC)


 * No, SpaceShipOne and Two need their feathering systems for re-entry; they activate it at re-entering the atmosphere in order to radically reduce speed, otherwise they would burn with more than Mach 3. The feathering system is deactivated in upper stratosphere with then having a speed of app. Mach 1.1. So the feather system is an alternative to a heat shield, but how did X-15 descent? --212.186.14.29 (talk) 19:40, 25 October 2016 (UTC)


 * Spend a little time reading the section North American X-15. The article discusses the fact that the wedge tail increased drag (good for landing), and tail flaps were used as air brakes, which is in effect what the "feathering system" does. The point is, no "heat shield" is necessary in this case, even on SpaceShipOne and Two. The relatively slow, gradual deceleration on descent (compared to say the Mercury capsule) does not generate a large heat load (see Atmospheric entry. JustinTime55 (talk) 20:22, 25 October 2016 (UTC)


 * Alright, this is what I wanted to know, thanks! --212.186.14.29 (talk) 08:36, 26 October 2016 (UTC)
 * Also note that the X-15-A2 was equipped with a complete heat-resistant ablative coating. Mojoworker (talk) 16:15, 22 November 2016 (UTC)