Starfighters Inc. F-104 - new satellite launcher

[edkyle99]

Pegasus has two issues, mainly being a pretty crappy LV mated with a not-very efficent launch method which is why Orbital has moved to the more standard Tarus model VTO LV.

Wrong on both counts

It is not crappy.  It is practical and more efficient of it payload class.

No, OSC did not move to Taurus for efficency, it did to meet a contract and to increase performance.  The change is no different than Delta II using larger SRM's. 

Not to mention that Orbital didn't really "move" to Taurus from Pegasus.  The company launched four Taurus rockets during the 1990s, and four more during the 2000s (not counting this year's Taurus - we're in the "2010s" now!).  It launched 24 Pegasus (Pegasi?) during the 1990s and 12 during the 2000s. 

On the other hand, the company did launch only one Minotaur to orbit during the 1990s, compared to eight during the 2000s.  Some of those Minotaur 1 payloads might have been made to fly Pegasus if Minotaur 1 didn't exist.
 
 - Ed Kyle

[Skyrocket]

This proposal reminds me of the ALSOR (Air launched sounding rocket) concept, where a Viper sounding rocket was air launched from an F-104.

[zaitcev]

The question is the amount of changes, in ALSOR-like case. Ishim was based on a pre-exising ASAT-like system. Its carrier MiG-31 had to be modified with additional wingtip fins in order to increase the yaw stability at maximum altitude (pictured at trials without the missile).



If it is permissible to modify the airplane, then belly mount like ALSOR is acceptable.

[RanulfC]

Pegasus has two issues, mainly being a pretty crappy LV mated with a not-very efficent launch method which is why Orbital has moved to the more standard Tarus model VTO LV.

Wrong on both counts

It is not crappy.  It is practical and more efficient of it payload class.

No, OSC did not move to Taurus for efficency, it did to meet a contract and to increase performance.  The change is no different than Delta II using larger SRM's. 

::::sigh::::Whatever Jim...

It IS "crappy" given it turns a solid-fuel (marginal ISP and pretty lowsy overall propellant margin) rocket into a rocket-PLANE and then adds all the various bells-whistles-and-subsystems needed to go from being an airplane to a near-vertical rocket. Oh it "looses" the extra-gear eventually but not until they have already penalized the overall performance. Granted, (as I noted) nobody really KNEW better at the time but Pegasus has proven NOT to be very economic LV overall. That however is NOT the fault of it being air-launched.

As for being "practical and more efficient of it(s) payload class" that is not a very effective argument since it IS just about the only orbital LV with a payload class that small! It never managed to fully capture (or grow) the small payload market because of the expense.

As for the Taurus, why don't we get the facts straight? The vehicle is the full-up Pegasus without its wings and ancillery equipment used for air-launch mounted on a Castor-120 first stage. I like the idea that you have Jim that "OSC did not move to Taurus for efficency" when that is EXACTLY what they did in order to INCREASE the performance (efficency) of the Pegasus to allow for more payload! (Having a contract from Boeing and DARPA to build the whole set up helps a lot)

And of course the entire process is VASTLY different than "adding-SRBs-to-the-Delta-II" since it went from a horizontal lift-supported 3STO air-launched vehicle to a 4STO "conventionally" launched vehicle with a large solid booster rocket in place of the aircraft.

Now if they had "simply" replaced the L-1011 with a JELAC-stage or a POGO THEN you could say it was similar...

Randy

[douglas100]

I don't mind constructive criticism, but calling Pegasus "crappy" is an insult to everyone at Orbital who designed and built it. Dr. Elias sometimes posts on this forum. Maybe you could email him and tell him how inferior his vehicle is.

[Jim]

::::sigh::::Whatever Jim...

It IS "crappy" given it turns a solid-fuel (marginal ISP and pretty lowsy overall propellant margin) rocket into a rocket-PLANE and then adds all the various bells-whistles-and-subsystems needed to go from being an airplane to a near-vertical rocket. Oh it "looses" the extra-gear eventually but not until they have already penalized the overall performance. Granted, (as I noted) nobody really KNEW better at the time but Pegasus has proven NOT to be very economic LV overall. That however is NOT the fault of it being air-launched.

As for being "practical and more efficient of it(s) payload class" that is not a very effective argument since it IS just about the only orbital LV with a payload class that small! It never managed to fully capture (or grow) the small payload market because of the expense.

As for the Taurus, why don't we get the facts straight? The vehicle is the full-up Pegasus without its wings and ancillery equipment used for air-launch mounted on a Castor-120 first stage. I like the idea that you have Jim that "OSC did not move to Taurus for efficency" when that is EXACTLY what they did in order to INCREASE the performance (efficency) of the Pegasus to allow for more payload! (Having a contract from Boeing and DARPA to build the whole set up helps a lot)

::::sigh::::Whatever, just another imposter posing as someone with knowledge of  spaceflight  facts. 

Solid launch vehicles are not crappy.  They have their place.  Not every vehicle is performance driven.  As for economic, name one small launch vehicle that is.  The airplane gear does not penalize the vehicle anymore than any other method of airdropped vehicles.

Here are the straight facts wrt Taurus.
Increasing the efficiency of a launch vehicle involves changes to propellant types, ISP changes in engines, weight reduction, etc. 
Increasing the efficiency of a launch vehicle doesn't not include wholesale swapout of first stages, which makes it a completely different launch vehicle.

Castor 120 for L-1011 is a change in the basic vehicle, it doesn't matter that the upperstages are from a Pegasus. It is a different vehicle and not a more "efficient" Pegasus.

Taurus is no more a Pegasus than a Minotaur II/III is
Just as Atlas Able and Thor Able were not Vanguard launch vehicles

If one were to compare efficencies of launch vehicles, it would not be Taurus vs Pegasus
it would be Taurus vs Minotaur IV vs Athena I
and
L-1011/Pegasus vs L-1011/X-34.

[RanulfC]

I don't mind constructive criticism, but calling Pegasus "crappy" is an insult to everyone at Orbital who designed and built it. Dr. Elias sometimes posts on this forum. Maybe you could email him and tell him how inferior his vehicle is.

If he posts here, I'm sure someone will bring it to his attention

The Pegasus was a "point-design" vehicle built to specific details, paid for by the Air Force AND Orbital. They did the best they could with what they had at the time. They COULD do much better, but it costs and Orbital can't afford it. Recall please that they (Orbital) also built the X-34s specifically to research (according to NASA contract) RLV economics and dynamics. Now that NASA is (possibly) going to allow someone to re-commision and actually fly the X-34s perhaps they can gain some of that experiance.

Solid launch vehicles are not crappy.  They have their place.  Not every vehicle is performance driven.  As for economic, name one small launch vehicle that is.  The airplane gear does not penalize the vehicle anymore than any other method of airdropped vehicles.

Yep they are "crappy" overall and while they have their "place" being a launch vehicle and being economical isn't and never has been "one" of them.

A small launch vehicle that is "economical" let me think... Hmmmm, I believe I noted that there AREN'T any so that's not really possible is it?

And yes, the "airplane" gear hurts the Pegusus more than "other" air-drop methods:
http://mae.ucdavis.edu/faculty/sarigul/aiaa2001-4619.pdf

You'd get better performance dropping a wingless-Pegusus out the back of a C-130 on a cargo-pallet the same way we do with the single and two-stage manuever vehicles used for ABM testing!
http://www.govsupport.us/navynepahawaii/Docs/024-DevDemonstrationLongRangeArLauTagSys,EA,Oct02.pdf
url]http://www.crc.com/LRALT.htm[/url]

Again though they were working with what they knew THEN, but we KNOW better now.

Finally I may not be an "expert" Jim but at least I try and stay consistant:
You said initially in comparing the "move" from the L-1011/Pegasus to the C-120/Tarus:

The change is no different than Delta II using larger SRM's.

I had issues with this comparison but NOW you say:

Castor 120 for L-1011 is a change in the basic vehicle, it doesn't matter that the upperstages are from a Pegasus. It is a different vehicle and not a more "efficient" Pegasus.

So... it's NOT like "larger" SRMS on the Delta-II now IS it?

Lets get the "facts" straight here in that Orbital itself calls the Taurus "a Ground-launched VARIANT of the Pegusus Launch Vehicle"
http://www.orbital.com/NewsInfo/Publications/Taurus_fact.pdf

They IN FACT used a wingless "Pegusus" in the design to REDUCE the overall work to meet the Boeing/DARPA requirements.

The Taurus IS a more efficent, higher capability Pegusus which is exactly what OSC set OUT to make.

I may not be an "expert" like YOU Jim but I DO try and gets my facts straight.

BACK on "subject" if the F-104s can be "refitted" with something like the original "GENIE" launch racks (which extended the missiles out and away from the aircraft prior to ignition) the aircraft then could take the majority of the "load" for the zoom allowing a more efficent LV to be carried but the limit is still going to be the ground clearance.

Overall it looks like around 20 inches or less diameter for the LV and probably around 6 feet long.

Randy

[simonbp]

Btw, a nice Wiki pic of Italian F-104s with Sparrows: http://en.wikipedia.org/wiki/File:F104s.jpg

Heh; that shows just how big the Sparrow is relative to the F-104. The aircraft must noticeably jump up when it release the missile...

[Jim]

[quote author=douglas100 link=topic=25260.msg749257#msg749257

1.Lets get the "facts" straight here in that Orbital itself calls the Taurus "a Ground-launched VARIANT of the Pegusus Launch Vehicle"
http://www.orbital.com/NewsInfo/Publications/Taurus_fact.pdf

2.They IN FACT used a wingless "Pegusus" in the design to REDUCE the overall work to meet the Boeing/DARPA requirements.

3.The Taurus IS a more efficent, higher capability Pegusus which is exactly what OSC set OUT to make.

I may not be an "expert" like YOU Jim but I DO try and gets my facts straight.

1. I guess you are swayed by simple marketing blurbs vs facts

2. The facts are that it doesnt reduce the overall work

3.  Higher capability does not equate to higher "efficiency"

[Jim]

The change is no different than Delta II using larger SRM's.

I had issues with this comparison but NOW you say:

Castor 120 for L-1011 is a change in the basic vehicle, it doesn't matter that the upperstages are from a Pegasus. It is a different vehicle and not a more "efficient" Pegasus.

So... it's NOT like "larger" SRMS on the Delta-II now IS it?

The comparison to Delta II SRM's was counter your inaccurate use of the word efficiency.  Using the same type of propulsion system but only making it larger is not increasing efficiency whereas changing the propellant composition to one of higher ISP in the same casing is.