Talk:Northrop Grumman Pegasus/Archive 1

Archive 1

Air vs. Ground Launch

Can anyone explain in this article what the advantages of air-launch are as opposed to ground launch? — Preceding unsigned comment added by 163.181.251.10 (talk • contribs) 23:18, 22 March 2006 (UTC)

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. — Preceding unsigned comment added by 83.73.103.23 (talk • contribs) 17:05, 12 July 2006 (UTC)

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)

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)

Currently there is no explanation of what is the "Hybrid" version in the article. Is that something that should be included? AmigaClone (talk) 10:52, 15 April 2020 (UTC)

What is the rocket supposed to do?

I have read the article and I understand that it is an article about a rocket that is launched from an aircraft while airborne. However, I have still to understand what the point of the rocket is? I mean: what does it do? Perhaps this should be clarified in the article? Preferably in the beginning. --Law Lord (talk) 08:58, 20 October 2008 (UTC)

I expanded the intro. I hope that helps. Ikluft (talk) 10:56, 1 November 2008 (UTC)

Staging point

Quoting this article: "Bad weather is still a factor during takeoff, ascent, and the transit to the staging point."

The meaning in our article Staging Area is "A staging area (or staging point) is a location where organisms, people, vehicles, equipment or material are assembled before use."

In this article, does "staging point" mean the airfield from which the airplane and rocket take off, or the place aloft where the stages begin to separate? Thanks, Wanderer57 (talk) 20:38, 15 June 2012 (UTC)

By weight, Pegasus is one of the most expensive air "launch-to-orbit" vehicles

This line confuses me. Isn't Pegasus the only operational air-launch-to-orbit system in history? If so, how could any other system be cheaper when there aren't any? Rob (talk) 20:04, 20 April 2013 (UTC)

Citations

The sections “Launch profile” and “Carrier aircraft” don't seem to cite any sources. Could someone please add sources?--Solomonfromfinland (talk) 03:45, 13 March 2016 (UTC)

Charts

The charts used here can be hard to interpret for people with color vision deficiency AKA colorblindness. This means at least 5% of the readers will have difficulty with the charts (more if the readers are mostly male. For a severely red-green colorblind person like myself they are totally incomprehensible. Could someone familiar with this type of accessibility please correct them. Because not all colorblindness is the same I am not able to do it myself. RMoribayashi (talk) 18:34, 17 April 2018 (UTC)

Apologies, they were mostly a test to just get that data in one place so the charts could be refined later. I'm going to have to fix a couple of these pages after some other work. We recently had a discussion on color-blindness and these charts over on the Falcon 9 launch talk page. @Insertcleverphrasehere: or @JFG: do you have any suggestions on these charts? Cheers! UnknownM1 (talk) 23:57, 17 April 2018 (UTC)

Use a snapshot in the colour blind simulator to check. There are issues with the first two graphs for all three (red-blind, green-blind, and blue-blind). Swap colours until it works. Use lightness and darkness more than colour where possible. I also removed a few redundant images that were messing up the charts. — Insertcleverphrasehere ^{(or here)} 00:51, 18 April 2018 (UTC)

@RMoribayashi:, Would you mind checking out the charts at List of Falcon 9 and Falcon Heavy launches to let us know if you have any difficulties with any colour pairs? Simulations only work so well, and we could use someone with your particular set of skills to check. Thanks. — Insertcleverphrasehere ^{(or here)} 00:55, 18 April 2018 (UTC)

Quite a difference. Using colors far enough apart in hue and brightness like those works well. While I have only one of the many types of CVD it's one of the more common and while many people are barely affected by their colorblindness I essentially live in a blue/green world. I guess that makes me a good guinea pig. I'd be glad to help.RMoribayashi (talk) 12:38, 18 April 2018 (UTC)

Orbital Boost Vehicle

OBV (Orbital Boost Vehicle) is a wingless Pegasus launch from the ground (see http://space.skyrocket.de/doc_lau_det/obv.htm). Should this be listed under Related projects or a version of the Pegasus? Mattise135 (talk) 18:57, 7 June 2018 (UTC)

Original research? The "private funding" and "did not receive any government funding" is a bit excessive

I just added a WP:OR cleanup tag to the article. It seems that there is a good bit of WP:SYN synthesis in the claims that relate to the fully private nature of the development of this rocket. For example, this one:

• "the development project was funded by Orbital Sciences Corporation and Hercules Aerospace, and did not receive any government funding."

All of the sources seem to be company published or company-written/company-articulated. So the view is a valid view; it's just a view and a position taken by the companies involved. Originally this was Orbital Sciences Corporation and Hercules Aerospace; today it is the successor after various mergers and acquisitions since the late-1980s/1990s: Northrop Grumman

At a minimum, we need better sources, and sources not directly tied to the company (primary sources), to establish the veracity of the claims being made about the magnitude of the "private development" of this technology. For example: the single paragraph in the source (Pegasus First Mission Flight Results, a paper presented via the AIAA by Mosier, Harris, Richards, Rovner, and Carroll) that discusses project funding says the company joint venture was privately funded, and that the jt. venture funded vehicle development; but is also quite explicit that the US government funded much of the non-recurring and recurring costs for Pegasus rocket testing and flight missions. Moreover, that is a company-authored paper, as all five of the authors are from the two companies; it is a good paper, but it is not a peer-reviewed journal article, and is not a WP:SECONDARY source. N2e (talk) 03:35, 4 May 2021 (UTC)