in 1957 Marin proposed the Titan-C based on Titan 1 hardware.
first stage 4 meter ø with 4 x Engine LR-87-3, second stage same like Titan 1 first stage
On 27 July, 1958 Herbert York director of defense research and engineering
considert Titan-C as Launch rocket for NASA and USAF. (Dyna Soar)
the Air Force's Titan C proposed by the Glenn L. Martin Company as a launch vehicle for Dynasoar.
The first-stage was 4 meters in diameter and was powered by four Aerojet ICBM engines of 667 kilonewtons (150 000 lb thrust) each.
The second stage was powered by two of the same engines but equipped with larger nozzles for high-altitude operation.7
Source:
Telephone interview with James Powell, formerly of Glenn L. Martin Co. and responsible for the Titan C concept, now at the Energy Research and Development Administration, Washington, 17 Sept. 1975.
http://www.hq.nasa.gov/office/pao/History/SP-4404/ch12-3.htm
http://www.hq.nasa.gov/office/pao/History/SP-4404/ch11-5.htm
in the End NASA take Saturn I, USAF the Titan-II
Martin reused name Titan-C for a Titan-II first stage and Lox/Lh2 Second stage for Dyna Soar
in end win Titan IIIC (Titan-III with Solid Booster) for Dyna Soar
Bigger Atlas : Helios
Kraft Ehricke made study for Heavy Lift rocket
in princip like Atlas but
use of 4 big LoX/Lh2 Booster engine with Lox tank in Boosterstage
Main engine is a NERVA with 12 Gw power with Lh2 Tanks
the Helios start chemical up to 40 km high dropped booserstage and Start Nuclear Engine
http://www.astronautix.com/lvs/helios.htm
another Big Titan : Barbarian
1986 Marin prposed for SDI
a 4.57 m diameter Titan vehicle with four LR-87 engines on the first stage,
and a single LR-87 engine on the second stage.
(again Titan-C this time with Titan-II hardware)
Another variant reportedly consisted of 5 Titan 4 SRM's, clustered around a 5.8 m diameter core.
This core would use 5 LR-87 engines, with tankage fabricated on Shuttle external tank tooling.
The third stage would utilize a single LR87 engine.
http://www.astronautix.com/lvs/barianmm.htm
Picture from Astronautix
