Talk:Lockheed Martin X-33

Not VentureStar

The VentureStar & the X-33 are two completely different spacecraft. This article is about the Lockheed Martin's X-33, IT SHOULD STRICKLY BE ABOUT THE X-33, NOT THE VENTURESTAR! References to VentureStar should been kept to an absolute minimum.--aceslead 03:49, 21 June 2006 (UTC)

The Other Bids

Boeing & McDonald Douglas each had a seperate bid for the X-33. More of the bids should be mentioned.--aceslead 03:28, 21 June 2006 (UTC)

Reliability

Conventional airplanes are 0.9999999999 reliable? That's 1 accident in 10 billion flights, which would mean 1 mishap in 100 years of flight, assuming there were 274,000 flights daily. 71.205.107.239 00:10, 12 October 2006 (UTC)

Stub Article?

The stub article heading has been removed since "14:59, 24 November 2006", but the article was still in the "1990s aircraft stubs" category.Annekcm 15:51, 20 March 2007 (UTC)

X-33 in Fiction

An X-33 type SSTO project is central to Michael Flynn's "Firestar" novel, with many references to the X-33 and its cancellation.

BobShair 04:03, 27 October 2007 (UTC)

X-33 / VentureStar confusion

(Originally posted on User talk:Fnlayson)

The "confusion" I see in the article includes:

First Photo with caption: “Simulated view of the X-33 in low earth orbit”

(Not at <75.8 km altitude and < Mach 13 of X-33 Environmental Impact Statement!)

While the X-33 would not approach airplane-like safety, the X-33 would attempt to demonstrate 0.997 reliability, or 3 mishaps out of 1,000 launches, which would be an order of magnitude more reliable than the Space Shuttle system.

(This reliability can't be demonstrated during the 15 flights covered by the EIS)

The X-33 was to be the first unmanned commercial aircraft to fly into space (75.8 km altitude).[3] It also was to be the first aircraft with a ballistic trajectory. It was to be launched upright like a rocket and rather than having a straight flight path it would fly diagonally up for half the flight, reaching extremely high altitudes, and then back down for the rest of the flight. It was intended for long inter-continental flights and supposed to be in service by 2012, but unfortunately the project was ceased.[citation needed]

(With my additions (unmanned and 75.8 km altitude). Is there such a thing as an “Unmanned Commercial Aircraft”, let alone a commercial aircraft flown on only 15 experimental NASA hops? Space is not normally expected to include flights below 75.8 km (from the EIS), although one official definition sets 50 km as the boundary. The EIS for the EXPERIMENTAL X-33 certainly does not include inter-continental flights let alone “in service by 2012.)

Construction of the prototype was some 85% complete ...

(An X-Plane doesn't HAVE a PROTOTYPE, since it is the Prototype, a one off (or small number of copies) assembly to prove a theory or investigate an idea.)

The X-33 in fiction...

(Every application in fiction built on the confusion LM deliberately generated between the funded X-33 suborbital project, and the unfunded, hypothetical VentureStar project.)

I confess to being hypersensitive to this error, having worked with a group in Texas who spent a great deal of time, effort and money on a Spaceport proposal (one of more than 20 nationwide) fully believing that the X-33 WAS the prototype for an ORBITAL vehicle, and that the development of a Space Shuttle replacement was well underway. These professionals could never believe my telling them that the funded X-33 project was for an unmanned, radio control model which would never go into space.

Beyond this, the LM planted confusion is widespread today, with the large majority of people believing that the X-33 was to be an orbital system (not a technology demonstrator which, if successful, could lead to the design and funding of an actual orbital test vehicle, which, if also successful, could lead to the funding and development of a vehicle which could actually carry passengers into space.

This article is actually very informative and well written. It does describe the X-33 reality, but the image and other comments noted serve to sustain the confusion deliberately created by LM rather than correct the misunderstanding. I see that my prior statement was a exaggeration, but I would like the Wiki article to end the LM intentional confusion with clear truth. Rpspeck (talk) 03:31, 6 February 2008 (UTC)

Risky extrapolation

Risky extrapolation would have been necessary to apply the results of successful tests (if these had ever occurred) to an orbital vehicle.

The cited Environmental Impact Statement makes no mention of extrapolation whether risky or not. This sentence should be removed unless a better citation can be found. —Preceding unsigned comment added by 131.252.209.209 (talk) 06:44, 26 December 2008 (UTC)

alt.space

I pulled this text from the tankage discussion"

This conclusion is heavily disputed in the alt.space community, who blame the program's failure on NASA's preference for researching new materials and technologies rather than using older more reliable ones—for example, use of composite hydrogen tanks instead of aluminum-lithium.

I feel that a usenet group doesn't meet real standards for inclusion here. Does anyone either a. disagree and/or b. have a better source for the sentence above? - CHAIRBOY (☎) 20:22, 21 March 2010 (UTC)

The sentence was uncited and tagged accordingly. So any source would be better. That opinion is probably not limited to just a user net group. Either way it needs to be cited. It can stay removed until it is.. -Fnlayson (talk) 20:27, 21 March 2010 (UTC)

Jess Sponable told me that directly in a conversation at Space 2002 in Albuquerque. Unfortunately, I don't have a citation either. Voronwae (talk) 15:29, 10 May 2012 (UTC)

clarify continued development?

first paragraph

Failures led to the cancellation of the program as a federal program in 2001, but Lockheed Martin has continued further testing, and has had successes as recently as 2009.

later in the article

Lockheed Martin deemed that continuing development of the X-33 privately without government support would not be profitable.

this sounds like lockheed canceled development. i know "determining it to be unprofitable" isn't the same as canceling it, but why is the sentence even included then? no one's paying them to develop it, duh it won't be profitable.

also the apparent recent continued development appears unrelated to the X-33. the X-33 is characterized by a lifting fuselage and a linear aerospike rocket nozzle. neither of these apply to the craft recently tested. lockheed says right now the project unnamed. —Preceding unsigned comment added by 98.112.150.220 (talk) 01:54, 16 April 2010 (UTC)

I'm going to go ahead and remove the last section. It's misleading, and the craft in question has turned out to be a reusable flyback booster for the Air Force reusable booster program. Voronwae (talk) 15:31, 10 May 2012 (UTC)

"Failures of its 21-meter wingspan"?

I don't see how a "wingspan" can fail, and there is no other mention of wings on the page. PapayaSF (talk) 05:29, 13 July 2017 (UTC)

Where to describe the other two proposals for X-33

Could be here or in a non redirect X-33 ? or in a non-redirect version of Reusable Launch Vehicle program (NASA) ? - Rod57 (talk) 00:11, 9 January 2018 (UTC)

Given that the article is relatively short at this point, I'd start by adding information here. Once such a section begins to overwhelm the rest of the article, about a third to half, then it could be split out to a separate article. (If you already have that much information to add, then go ahead and start the new article now.) Reusable Launch Vehicle program would probably be the best title, as no disambiguation is currently needed. - BilCat (talk) 01:07, 9 January 2018 (UTC)

NASA images

The NASA image in [1] is copyright free and we could use it (I don't know how to put in Wikimedia) - Left to right the image shows the concepts from Rockwell, McDonnell Douglas, and Lockheed Martin. - Rod57 (talk) 00:11, 9 January 2018 (UTC)

What can we say about the metallic heat shield/TPS

Since it was an important part, even of the sub-scale X-33, what can we say about it ? What alloys ? What size sheets ? How fixed to the body ? - Rod57 (talk) 14:26, 1 May 2020 (UTC)

The metallic TPS was considered developed and ready by Feb 1999 : [2].

Blosser 1998 has details : eg. Inconel 617 honeycomb sandwich over silica fibres and titanium in foot square tiles. - Rod57 (talk) 23:17, 29 August 2020 (UTC)

Safety compared to the Space Shuttle

The article claims the 3 in 1000 reliability would be an order of magnitude better than the Space Shuttle. That would be 1 in 333.

The shuttle was 2 in 135, or about 1 in 68. NASA's analysis late in the program put the LOC at 1 in 90.

1 in 333 is 4.9x better than 1 in 68. It's only 3.7 x better than 1 in 90.

Neither of those are an order of magnitude. EricGunnerson11 (talk) 23:45, 7 October 2023 (UTC)

Corrected typo

I corrected an apparent typo in the history to read, ‘reusable’ from ‘resusable’. 141.226.232.68 (talk) 21:12, 4 May 2024 (UTC)