Talk:Pegasus rocket

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Under a proposal to clean up inconsistent disambiguation of rocket article titles, this article, Pegasus rocket, may be moved to Pegasus (rocket). At this stage, it is only a proposal at an early stage of discussion, but you are encouraged to contribute to the discussion, which is located here.

[edit] Air vs. Ground Launch

Can anyone explain in this article what the advantages of air-launch are as opposed to ground launch?

[edit] Verification of Cost

Can anyone verify the launch cost quoted? it seems way too high to me. An example press release from Orbital: http://www.orbital.com/Template.php?Section=News&NavMenuID=32&template=PressReleaseDisplay.php&PressReleaseID=560 seems to suggest that the price in the wiki page is exaggerated.

Unfortunately both numbers are "right"; the cost of a launch is not as easy to define as the cost of, say, a car, since exactly what is included in "a launch" varies. For the launch of a commercial communications satellite to geosynchronous orbit, exactly what is being purchased is very, very carefully defined and therefore its cost is also well defined. This is not usually the case with other launches. The hardware associated with a Pegasus launch vehicle, plus the labor associated with assembling and testing it is significantly less than half the $30M amount quoted in the article. Maintaining the launch team and its equipment (such as the L-1011) and recovery of the development costs add a few million given the relatively low launch rate of Pegasus. Profit for government services such as launches is usually between 8% and 10% but can vary. The launch range charges about $1.5M per launch for its services. Government agencies usually incur additional costs such as mission planning and a fair share of the annual cost of the government office that buys and supervises launch services. The $30M cost mentioned is the average amount that NASA allocates to "launch costs" on a Pegasus-based NASA mission, not the amount NASA pays Orbital.-- AntonioElias 22:30, 9 May 2007 (UTC)

[edit] Doesn't seem to match Encyclopedia Astronautica

I was glancing through the Encyclopedia Astronautica and they show about a factor of three less flights (only 11 total) than Wikipedia does. It's clearly the same vehicle. And there's other weirdness. They list one flight in 2004, while Wikipedia lists none for that year. What is up? -- KarlHallowell 21:24, 5 March 2007 (UTC)

Encyclopedia Astronautica distinguishes between the original or "short" version of Pegasus and the long-motor version ("Pegasus XL".) Company (Orbital) records show that as of 26 April 2007 UTC there have been 9 "short" launches and 28 XL launches, as well as one "hybrid" (long first stage, short second stage) for a total of 38 Pegasus launches to orbit. The article cited above lists the 9 "short" launches, the only "hybrid" launch and one of the three HyperX non-orbital flights that used only the first stage of a Pegasus (this being the "extraneous" 2004 flight; there were no Pegasus launches to orbit in 2004). The second HyperX non-orbital flight is counted among the XL launches in the Pegasus XL entry of Encyclopedia Astronautica. For some reason the third HyperX flight on 16 November 2004 is missing from the article. -- Antonio Elias 21:44, 9 May 2007 (UTC)

With all due respect to Antonio, a slight correction to his statement above. The "Hybrid" version of Pegasus (or what Encyclopedia Astronautica refers to as Pegasus H) actually refers to a Pegasus Standard (or "short" Pegasus) with canted fins (identical to the Pegasus XL fin design) so that the vehicle can be flown from the L1011. The canted fins are necessary to clear the L1011 landing gear doors. Technically, Pegasus Standard vehicles were only flown from the B-52. All Pegasus vehicles flown from the L1011 have been either Pegasus XL's or Pegasus Hybrid's. Orbital's Pegasus Mission History webpage actually incorrectly lists several missions as Pegasus Standard vehicles when they were in fact Pegasus Hybrid vehicles. Appendix E of the Pegasus User's Guide is a better source. There have not been any Pegasus vehicles with a long first stage and a short second stage. TimR121 20:26, 19 June 2007 (UTC)