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==F-5 connection==
==Conclusion==
One thing the article would benefit from is a short paragraph explaining what the programme achieved, and why it came to an end. Presumably the X-29 was never supposed to be an actual operational fighter jet, but it's not clear from the article what came of all the research (I assume that NASA and Grumman concluded that swept-forward-wing designs were more trouble than they were worth, but of course this kind of thing is probably tricky to research). -[[User:Ashley Pomeroy|Ashley Pomeroy]] ([[User talk:Ashley Pomeroy|talk]]) 23:30, 26 March 2010 (UTC)
According to this link in the article, [http://www.fighter-planes.com/info/x29.htm http://www.fighter-planes.com/info/x29.htm]:
:''The two X-29s were built to test a forward-swept wing of composite structure. The X-29 incorporates the forward fuselage of the F-5 and the landing gear of the F-16.''


== Article lacks avionics, communication, and ground control ==
This agrees with other sources I have read over the years, at least one print source of which I still have. The "forward fuselage" (basiaclly the cockpit to just aft of the nose cone) is hardly the "airframe". From what I have read, the X-29 was a new design which just used existing structures which did not need to be purpose built, including the main gear of the F-16. I certainly hope the X-29 doesn't show up on the F-16 page as a variant, or even in related content. However, I have no problem listing the F-5 under Related development in the Related content section. - [[User:BillCJ|BillCJ]] 20:50, 17 January 2007 (UTC)
The article needs more on avionics, communication (data), and ground control. The plane was not flyable solely by the pilot. This also limited range. [[Special:Contributions/198.123.53.107|198.123.53.107]] ([[User talk:198.123.53.107|talk]]) 20:29, 31 January 2013 (UTC)


:The aircraft had (I believe) triple redundance fly by wire that assisted the pilot in flying the aircraft. This aspect has nothing to do with the aircraft's range.
==Personal note==
:If you see a void in avionics, comms, and/or GC info, please feel free to add properly referenced information to your heart's content. [[User:Ckruschke|Ckruschke]] ([[User talk:Ckruschke|talk]]) 18:13, 1 February 2013 (UTC)Ckruschke


== Bit of a lack of balance to this article? ==
I used to make TDY trips to Grumman, for systems-level verificaiton tests. I was able to see/touch the X-29 #2 ship at Calverton sometime in the mid-80s. Until #1 was doing well in flight test, Grumman would not allow this. I felt privleged!
This is a very positive article. All of the wonderful things that the X-29 achieved. So ... why are there no commercial or even military FSW planes in existence? After all of this positive stuff, is there after all something flawed with the design? Are there hidden difficulties in building this on a larger scale? Difficult to believe that if there were no negatives about the X-29, that we don't have lots of FSW planes around. Think that there needs to be something at the end of the article about why this design never took off (if you'll pardon the pun). Coz at the moment the whole thing reads like a Grumman sales promotion. [[User:Old wombat|Old_Wombat]] ([[User talk:Old wombat|talk]]) 12:56, 30 April 2013 (UTC)


:There are many X-planes that did not end up as production aircraft in any shape or form. This should not be construed as a knock on either the X-29 specifically or the X program in general or the purpose behind creation/flight testing of these aircraft. I would wager that DARPA, Grumman, NASA, and the aircraft community at large learned alot about how carbon-fiber aircraft members react in flight and advanced fly-by-wire controls (just to name two things that the aircraft was testing) that were then utilized in later production airframes.
Also, there was a cartoon of the X-29. The crew chief, unfamiliar with forward swept wings, tells the test pilot "They put the seat in backwards, Sir, so I had to turn it around." {{unsigned|205.175.225.22}}
:As far as your comment about the article being a Grumman promo piece, I would ask that you point out specific items in the article that you feel are puffery or blatant promotion. [[User:Ckruschke|Ckruschke]] ([[User talk:Ckruschke|talk]]) 16:09, 30 April 2013 (UTC)Ckruschke


::Some of the operational service was written in a slightly flowery style, but I think I've sorted that. I don't see any particular puffery. [[User:GraemeLeggett|GraemeLeggett]] ([[User talk:GraemeLeggett|talk]]) 18:00, 30 April 2013 (UTC)
== Aeroelastic Considerations ==


==Saab JAS 39 Gripen==
Fnlayson, you left a note about whether the AIAA reference applies to both paragraphs in the aeroelastic section I added. Yes, it does. What's a good way to indicate that? Just repeat the reference after both paragraphs?
One must wonder if there was any connection between the X-29 and the [[Gripen]] programme? The swedish light fighter jet was developed in about the same mid-1980s timeframe, made use of the same F-404 engine and canard wings and the fuselages look quite similar. [[Special:Contributions/82.131.128.123|82.131.128.123]] ([[User talk:82.131.128.123|talk]]) 09:09, 19 August 2013 (UTC)


:I've never seen anything about a connection between the two programs of any kind. Yes, both use the same engine type, but it doesn't appear that the engine choice was in any way related, or a joint decision. One must assume the similarties are coincidental in the absense of any evidence of a connection between the two designs. By the way, talk pages are not forums for discussing the topic, but for how to improve the article itself. Your question itself is OK, but we really can't go into a detailed analysis of the similarities and differences between the designs here. - [[User:BilCat|BilCat]] ([[User talk:BilCat|talk]]) 10:05, 19 August 2013 (UTC)
The AIAA reference is available online through a Google Books preview, but I'm not sure if it's proper to put a link to the site. Is the Google Books preview static, or does it randomly select pages to remove? This is the link to the first relevant page: [http://books.google.com/books?id=vROcxJj4igQC&printsec=frontcover&source=gbs_summary_r&cad=0#PPA55,M1 Performance, Stability, Dynamics, and Control of Airplanes‎].

I found another good source, NASA Technical Memo 100445, [http://www.nasa.gov/centers/dryden/pdf/88141main_H-1500.pdf ''Current Flight Test Experience Related to Structural Divergence of Forward-Swept Wings'']. There's some info about the aerodynamics that create the divergence in the introduction, and probably some more encyclopedic info for anyone who cares to comb through it. Might take a look myself one day.

There's also a Popular Science article from 1980, also available in Google Books (apparently not as a preview, but the full issue): [http://books.google.com/books?id=kY7Uj6pCZ0oC&pg=PA72 ''Wrong Way Wings Aid Maneuverability of Supersonic Planes'']. It's maybe more accessible for the average reader, and does a decent job of explaining the aerodynamic bending/twisting coupling, but it doesn't really capture the effect in the composite material. Does it make sense to add one or both of these references? [[User:Khakiandmauve|Khakiandmauve]] ([[User talk:Khakiandmauve|talk]]) 07:25, 13 February 2009 (UTC)

: I must have forgotten about this. I fixed the AIAA reference to the first paragraph. I removed the decrease in buffet sentence from above the Aero section. -[[User:Fnlayson|Fnlayson]] ([[User talk:Fnlayson|talk]]) 18:34, 28 May 2009 (UTC)

== "In Popular Culture"/Videogames ==

The X29 appeared as the Grumman F29 Retaliator in the [[1990]] PC/Amiga game [[F29 Retaliator]], published by [[Ocean Software]].
I don't know if this is relevant enough for inclusion in the article, but I think I have seen some articles on aircrafts mentioned appearances in various video games and TV shows, and to my knowledge, F29 Retaliator is the only "official" video game appearance of this aircraft (though it also appeared in various unofficial mods for Microsoft's Flight Simulator series). <span style="font-size: smaller;" class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/213.89.231.149|213.89.231.149]] ([[User talk:213.89.231.149|talk]]) 22:51, 15 February 2009 (UTC)</span><!-- Template:UnsignedIP --> <!--Autosigned by SineBot-->
: Thanks for taking the time to ask first. It has to be a notable appearance to be added. Also, for this one need a reference saying it is really a X-29, vs. people saying it looks like one. See [[WP:WikiProject Aircraft/page content#Popular culture]] for more info on guidelines. -[[User:Fnlayson|Fnlayson]] ([[User talk:Fnlayson|talk]]) 00:07, 16 February 2009 (UTC)

== Decrease in Buffetting ==

Fnlayson, decrease as compared with what? Other forward swept wing aircraft operating supersonically? Conventional aircraft in the transonic region? [[User:Khakiandmauve|Khakiandmauve]] ([[User talk:Khakiandmauve|talk]]) 17:08, 28 May 2009 (UTC)
: I didn't write it, just changed to a more likely term. Since the X-29 has a forward swept, that's probably compared to a regular swept wing fighter. -[[User:Fnlayson|Fnlayson]] ([[User talk:Fnlayson|talk]]) 18:22, 28 May 2009 (UTC)
: The statement on "buffeting" is very vague: Buffeting from stall or buffeting from high Mach? Also, what to compare it with ? You can only compare it with a rearward swept plane with same aerodynamic profile, same wing area etc. Also, the electronic flight control system will surely play a role in evening out any "rough" behaviour of the aircraft... so is it really an aerodynamic effect ..? In any case, a source should be provided.--[[User:Iediteverything|Iediteverything]] ([[User talk:Iediteverything|talk]]) 18:30, 28 May 2009 (UTC)

== Dynamic instability ==
A sentence in the article states that "the wing configuration made the craft inherently unstable". This statement can easily be misunderstood in the way that one might think the rearward sweep rendered the aircraft unstable. However, the instability is only due to the relative positions of CG, canard and wing. I propose to clarify the statement.--[[User:Iediteverything|Iediteverything]] ([[User talk:Iediteverything|talk]]) 19:28, 28 May 2009 (UTC)

: Some clarifying would be good. But there are other articles to really explain what unstable/instability means. Articles such as [[Relaxed stability]], and [[Longitudinal static stability]] are some I found on this. -[[User:Fnlayson|Fnlayson]] ([[User talk:Fnlayson|talk]]) 13:13, 29 May 2009 (UTC)

: I agree. Also, as canard architecture would allow to have an orthodox stability with both the main wing and the stabilizer concurring to the lift (one of the many reasons to use relaxed stability with a standard geometry is to avoid the negative vector of the stabilizer push reducing the overall lift), the choice of making the aircraft using a relaxed stabilty model stems probably out of the wish to get the plane the most manouvrable possible, and is completely a designer choice.By the way, forward swept wings affects a little the directional stability, but it's nothing that requires anithing more than a bigger rudder. There have been some canard planes (starting with the Wright's) as well as some (moderately: torsion is a bad beast on these wings, and require top-notch tecnique - else this plane wouldn't have been needed) negative swept wings planes way before fly-by-wire cames into existence.[[Special:Contributions/79.152.135.56|79.152.135.56]] ([[User talk:79.152.135.56|talk]]) 18:54, 17 July 2009 (UTC)

==Similarity in appearance to the F-20 Tigershark==

Call me crazy but i think that the X-29 looks like an [[F-20 Tigershark]] with foward-swept wings and canards. - [[User:Blueteamguy|Blueteamguy]]

:Hmm, interesting observation...the resemblance is very striking. I wonder if the X-29 was based off the F-20 airframe? Would be interesting to find a good source connecting the two. <span style="white-space:nowrap">— [[User:Huntster|Huntster]] <small>([[User talk:Huntster|t]] • [[Special:Emailuser/Huntster|@]] • [[Special:Contributions/Huntster|c]])</small></span> 23:03, 2 July 2009 (UTC)

: The forward fuselage is from the F-5. This is mentioned above and in the article. -[[User:Fnlayson|Fnlayson]] ([[User talk:Fnlayson|talk]]) 23:17, 2 July 2009 (UTC)

::And the F-20 was based on the F-5, hence the striking similarity. Beyod that, the rest of the fuselage, the wings, and the contral surfaces are quite different. There is commonality in the engine, as both aircraaft used the GE F404, and thus the exaust nozzles are similar, as is the size of the rear fuselage that contains the engine. - [[User:BillCJ|BillCJ]] ([[User talk:BillCJ|talk]]) 06:01, 3 July 2009 (UTC)

== Citations needed eh? :-) ==

The edit by Fnlayson at 02:48, 1 September 2009 installed two "Citation Needed" tags. I removed one "Citation Needed" tag that was put in place after I changed one uncited claim to another uncited claim. It seemed to me that often the criterion for a tag is a mere ''change'' that happens to get a citationist's attention. I don't think this is the way things should be. Indeed, I noticed that the ''whole article'' is without inline citations. I don't know why those two sentences were singled out in the edit for a tag. I had made other uncited changes (based only on my memory from three years flight testing both airplanes) that were not tagged. It all seems haphazard, especially in light of the whole article being citationless. Anyway, this is just my defense for ''removing'' that tag that was added to one of my edits. I hope it works! :-)

--[[User:Gummer85|Gummer85]] ([[User talk:Gummer85|talk]]) 08:27, 1 September 2009 (UTC)

Okay, I take some of that back, the article isn't as citationless as I portrayed it. I added a (cruddy) inline citation (to the spot where I had removed the tag) referring only to the "Aeroelastic" part of the article itself. That should be good enough. It better be, dang it. :-)

--[[User:Gummer85|Gummer85]] ([[User talk:Gummer85|talk]]) 08:44, 1 September 2009 (UTC)

:I hate to tell you, but I had to remove the reference. We cannot, under any circumstance, reference an article on Wikipedia. It would be like a book on airplanes using itself as a source! If the citation used in that section is applicable in this particular spot, simply add the same citation here. <span style="white-space:nowrap; text-shadow:gray 5px 3px 1px;">— [[User:Huntster|Huntster]] <small>([[User talk:Huntster|t]] [[Special:Emailuser/Huntster|@]] [[Special:Contributions/Huntster|c]])</small></span> 09:08, 1 September 2009 (UTC)


::Gummer, I'm not sure excalty what you ''think'' Fnlayson was doing, but he is a good editor, and is following proper procedure per [[WP:RS]]. And Hunster is right that we don't cite WP articles, nd that the proper way to do that was to cite the source used in that section, assuming it says that. That's hard to know, since Gummer edited the section without providing new sources. One must assume he actually read the source, and was making a clarifiction based on that source. Also, Leads aren't meant for long drawn-out explanations; that goes in the main text. I've this restored the origian Lead. If what it says is incorrect, then correct it, keeping it concise, or take it out. - [[User:BilCat|BilCat]] ([[User talk:BilCat|talk]]) 10:48, 1 September 2009 (UTC)

Latest revision as of 18:43, 30 January 2024

Conclusion

[edit]

One thing the article would benefit from is a short paragraph explaining what the programme achieved, and why it came to an end. Presumably the X-29 was never supposed to be an actual operational fighter jet, but it's not clear from the article what came of all the research (I assume that NASA and Grumman concluded that swept-forward-wing designs were more trouble than they were worth, but of course this kind of thing is probably tricky to research). -Ashley Pomeroy (talk) 23:30, 26 March 2010 (UTC)[reply]

Article lacks avionics, communication, and ground control

[edit]

The article needs more on avionics, communication (data), and ground control. The plane was not flyable solely by the pilot. This also limited range. 198.123.53.107 (talk) 20:29, 31 January 2013 (UTC)[reply]

The aircraft had (I believe) triple redundance fly by wire that assisted the pilot in flying the aircraft. This aspect has nothing to do with the aircraft's range.
If you see a void in avionics, comms, and/or GC info, please feel free to add properly referenced information to your heart's content. Ckruschke (talk) 18:13, 1 February 2013 (UTC)Ckruschke[reply]

Bit of a lack of balance to this article?

[edit]

This is a very positive article. All of the wonderful things that the X-29 achieved. So ... why are there no commercial or even military FSW planes in existence? After all of this positive stuff, is there after all something flawed with the design? Are there hidden difficulties in building this on a larger scale? Difficult to believe that if there were no negatives about the X-29, that we don't have lots of FSW planes around. Think that there needs to be something at the end of the article about why this design never took off (if you'll pardon the pun). Coz at the moment the whole thing reads like a Grumman sales promotion. Old_Wombat (talk) 12:56, 30 April 2013 (UTC)[reply]

There are many X-planes that did not end up as production aircraft in any shape or form. This should not be construed as a knock on either the X-29 specifically or the X program in general or the purpose behind creation/flight testing of these aircraft. I would wager that DARPA, Grumman, NASA, and the aircraft community at large learned alot about how carbon-fiber aircraft members react in flight and advanced fly-by-wire controls (just to name two things that the aircraft was testing) that were then utilized in later production airframes.
As far as your comment about the article being a Grumman promo piece, I would ask that you point out specific items in the article that you feel are puffery or blatant promotion. Ckruschke (talk) 16:09, 30 April 2013 (UTC)Ckruschke[reply]
Some of the operational service was written in a slightly flowery style, but I think I've sorted that. I don't see any particular puffery. GraemeLeggett (talk) 18:00, 30 April 2013 (UTC)[reply]

Saab JAS 39 Gripen

[edit]

One must wonder if there was any connection between the X-29 and the Gripen programme? The swedish light fighter jet was developed in about the same mid-1980s timeframe, made use of the same F-404 engine and canard wings and the fuselages look quite similar. 82.131.128.123 (talk) 09:09, 19 August 2013 (UTC)[reply]

I've never seen anything about a connection between the two programs of any kind. Yes, both use the same engine type, but it doesn't appear that the engine choice was in any way related, or a joint decision. One must assume the similarties are coincidental in the absense of any evidence of a connection between the two designs. By the way, talk pages are not forums for discussing the topic, but for how to improve the article itself. Your question itself is OK, but we really can't go into a detailed analysis of the similarities and differences between the designs here. - BilCat (talk) 10:05, 19 August 2013 (UTC)[reply]