Titan IV Competitors

[Yellow Palace]

Some competitors to the Titan 34D7, which became the Titan IV, from the 1984 report 'Assessment of Candidate Expendable Launch Vehicles for Large Payloads'. I've not bothered copying the details of the Titan 34D7 as its' ultimate form is quite well known.

Source:
http://hdl.handle.net/2060/1985015556

Atlas II

The Atlas II/Centaur represents a redesign of the Atlas G. Its diameter is increased from 120 inches for the current Atlas to 200 inches. The Centaur G', which is being developed for the STS, will be used for the upper stage. The Atlas II propulsion system consists of 5 liquid rocket engines and 4 strap-on solid rocket motors, all of which use existing designs. The general concept for the Atlas II suggests that established technology and proven hardware will be used. The liquid rocket engines being considered for use are of proven lineage; their development was initiated over 30 years ago. Nevertheless, the Atlas II is structurally a new launch vehicle with corresponding risks.

Performance: 11,000 lbs to GEO from 80 x 104 nautical mile orbit

It's not obvious to me where the 67" SRMs were proven from - the diameter is similar to a Minuteman, but the first stage on that rocket is only about half the length of the Atlas II SRM. Heck, the SRMs are almost as large as an entire Minuteman.

SRB-X

The SRB-X launch vehicle system is also an assemblage of rockets Developed in other vehicles and proven in many successful flights. The first stage consists of 2 four-segment solid rockets identical with the first stage of the shuttle. The second stage is a three-segment variation of the first solid stage with a modification to the burning rate of the rocket fuel. The third stage is essentially an unmodified version of a standard Titan second stage. The upper (fourth) stage is a Centaur rocket identical to the one under development for the shuttle. However, because the first-stage Solid Rocket Boosters have been spaced to utilize STS launch facilities, development of a truss will be required making the SRB-X, like the Atlas II, essentially a new launch vehicle with some corresponding risks.

Performance: 11,500 lbs to GEO from 100 nautical mile circular orbit

I've seen this described as the 'single worst Shuttle-derived launch vehicle ever designed' which seems a bit strong, until you see what they had in mind for the thing. Yikes.

 

[Michel Van]

nice find RLBH
Atlas was build in that time by General Dynamics (Convair)
Was also the manufacturer of Saturn IB so therefore
the use of H-1 engine for Atlas II/Centaur proposal

in end became the Atlas II a modified Atlas G,
with engines with greater thrust and longer fuel tanks for both stages.
only with the Atlas V Lockheed build something similar to 1984 proposal

by the way, was there a Atlas IV proposal ?

 

[robunos]

When I try the link above,
I get 'Handle not found'...


cheers,
Robin.

 

[Yellow Palace]

When I try the link above,
I get 'Handle not found'...

Try this one, which goes through NTRS.
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19850015556_1985015556.pdf

 

[blackstar]

Some competitors to the Titan 34D7, which became the Titan IV, from the 1984 report 'Assessment of Candidate Expendable Launch Vehicles for Large Payloads'. I've not bothered copying the details of the Titan 34D7 as its' ultimate form is quite well known.

To be precise, these were alternatives for NASA. They were not alternatives for the USAF. Simply put, USAF was building this no matter what and NASA was asking if they had any alternatives to use instead of this rocket.

 

[Byeman]

To be precise, these were alternatives for NASA. They were not alternatives for the USAF. Simply put, USAF was building this no matter what and NASA was asking if they had any alternatives to use instead of this rocket.

Actually, the Atlas II was a USAF vehicle. There was a USAF competition between Atlas II and Titan 34D7. NASA tried to insert the SRB-X

 

[Byeman]

nice find RLBH
Atlas was build in that time by General Dynamics (Convair)
Was also the manufacturer of Saturn IB so therefore
the use of H-1 engine for Atlas II/Centaur proposal

in end became the Atlas II a modified Atlas G,
with engines with greater thrust and longer fuel tanks for both stages.
only with the Atlas V Lockheed build something similar to 1984 proposal

by the way, was there a Atlas IV proposal ?

The Saturn IB was built by Chrysler, not Convair. Excess H-1's were modified into RS-27's and these were the basis for the MA-5A booster engines.

No Atlas IV, because Atlas V combine Atlas III and Titan IV.

 

[Yellow Palace]

Actually, the Atlas II was a USAF vehicle. There was a USAF competition between Atlas II and Titan 34D7. NASA tried to insert the SRB-X

It may be that the USAF knew that it wanted the Titan 34D7, but needed to have a competition since it was a major new vehicle in either case. The report certainly states that the USAF had started procurement before the report was completed, which supports the position that the report was prepared for NASA rather than the USAF. Given that Cassini-Huygens was the only non-DoD Titan IV flight, it certainly seems like NASA keeping out of the CELV program was the right call.

 

[Byeman]

It may be that the USAF knew that it wanted the Titan 34D7, but needed to have a competition since it was a major new vehicle in either case. The report certainly states that the USAF had started procurement before the report was completed, which supports the position that the report was prepared for NASA rather than the USAF. Given that Cassini-Huygens was the only non-DoD Titan IV flight, it certainly seems like NASA keeping out of the CELV program was the right call.

NASA's use of the vehicle had nothing to do with it. Cassini would have flown on the shuttle if it were not for Challenger. NASA proposed the SRB-X to help keep shuttle costs down since it shared the SRB and launch base infrastructure. The USAF wanted a backup to the shuttle (which didn't use shuttle components) and didn't really care which of the two other vehicles won. Originally, the CELV program was to be only a 10 vehicle buy and for only selected east coast 10klb GSO missions such as Milstar. After Challenger, it went to 25 missions with west coast NUS configurations and an east coast IUS config. It later went up to 45 missions, down to 41 and finally 39.

 

[blackstar]

Actually, the Atlas II was a USAF vehicle. There was a USAF competition between Atlas II and Titan 34D7. NASA tried to insert the SRB-X

But the study of alternatives was done for NASA.