HL-42” Personnel & Logistics Vehicle the Might Have Been

“HL-42” Personnel & Logistics Vehicle The might have been

Giuseppe De Chiara

and

Dr. Theodore A. Talay

01.06.2013

All the drawings are copyright of the authors Foreword (1/2)

In response to a Congressional request, NASA Administrator Dan Goldin in January 1993 initiated a half-year multi-center Access to Space (ATS) Study to determine future US space transportation options. Three options were examined: Option 1 (JSC lead) examined extending the Shuttle through 2030; Option 2 (MSFC lead) looked at a conventional technology replacement of the Shuttle by 2005 using new expendables and reusable spacecraft; Option 3 (MSFC lead) studied advanced technology replacements of the Shuttle by 2008. Within Option 2 there were four architectures examined. These included several expendable launch vehicles and reusable spacecraft for crew and cargo transfer to the space station. Two options for the reusable spacecraft were a 70% scale Space Shuttle-type vehicle proposed by JSC and a 42% scaled up version of the HL-20 called HL-42 proposed by LaRC. As the study progressed the HL-42 was selected for the final architecture. Detailed costing of Option 2 was conducted to compare with the other ATS options. The HL-42 can be directly traced to the work done by LaRC on the HL-20 Personnel Launch System (PLS). In the period between 1983 and 1993 Langley Research Center, studied and tested the HL-20 lifting body design based on the external configuration of the Soviet Bor-4 spacecraft. Two study contracts by Rockwell International and the Lockheed “Skunk Works” defined the spacecraft to a level that development of the PLS could begin had NASA given an authority to proceed. Requirements for the HL-42 from the Access to Space study included carrying personnel and logistics to and from the space station. Additionally, the European Automated Transfer Vehicle (ATV) would also supply logistics. An on-orbit servicing version of HL-42 was also studied. A new booster design by MSFC in the 30 mT payload class for launching these spacecraft was based on a first stage using three RD-180 hydrocarbon engines and a second stage using one J-2S class engine. This booster could also be used to launch large space station elements as required.

“HL-42 Personnel & Logistics Vehicle”

The HL-42 was to use conventional technologies with a focus on efficient ground and flight operations. For example, the main structures were aluminum-lithium with a graphite polyimide heat shield substructure. OMS/RCS were to use LOX/Methane because of a no hypergolic propellant ground rule. Electromechanical actuators were used to move the control surfaces. The landing gear were to be modified from an F-15 fighter. The thermal protection system was insulation materials modified from the Shuttle. The pressurized cabin had frame extensions with upper removable access panels for simplified servicing on the ground. A 50-inch (1,27 m) rear hatch was to be used to load and unload of personnel and cargo such as space station racks and other logistics. Also, there was an ingress/egress hatch on top of the vehicle. In the event of an on-the-pad abort four large launch escape solid motors with thrust vector control burn for 4 seconds and thrust the HL-42 away from the booster at 8 g’s acceleration. There followed a 12-second burn of four lower thrust sustainer motors to get the HL-42 to a sufficient altitude to permit a landing at the KSC runway. Later in the launch an abort required an ocean landing by parachutes except near the end of the 2nd stage booster burn where a Trans-Atlantic Abort (TAL) or Abort To Orbit (ATO) was possible. For space station missions an option to abort to East coast runways was considered, but not studied in detail. Because of its 1,850 km (1,000 nmi) cross range capability on return from orbit, emergency runway landings could be possible from any orbit assuming five strategically chosen Shuttle capable runways were used. The nominal mission was, however, a KSC landing.

“HL-42 Personnel & Logistics Vehicle”

Drawings are at the same scale

Lockheed - Martin SPIRAL 50/50 MiG 105-11 Definitive version

BOR 4 LaRC Mock-up

North American SNC Dream Chaser Rockwell Proposal

HL-42 LaRC STAR Vehicle Proposal

1960 1970 1980 1990 Today

“HL-42 Personnel & Logistics Vehicle”

Source: NASA

“HL-42 Personnel & Logistics Vehicle”

Top view

Front view

Side view “HL-42 Personnel & Logistics Vehicle”

Top view

Front view

Side view “HL-42 Personnel & Logistics Vehicle”

Top view

Front view

Side view

“HL-42 Personnel & Logistics Vehicle”

HL-42: Crew: 4 Body Length: 12,8 m OverallLength: 13,8 m Wing span: 10,2 m L/D (Hypersonic): 1,4 Re-entry cross range: 1.850 km Habitable volume : 16,40 m 3 Launch Mass: 28.734 kg On orbit Mass: 21.100 kg Dry Mass: 13.367 kg Payload: 4.218 kg Engines: 4 OMS Propellants: LOX/Methane Specific impulse: 300 sec ∆v: 289 m/sec Top view Electrical System : Batteries/Fuel Cells Escape System: Solid Rockets w/TVC

“HL-42 Personnel & Logistics Vehicle”

Top view

Front view

Side view “HL-42 Personnel & Logistics Vehicle”

Main Features: Length: 62.0 m (HL-42 included) Max Diameter: 8.2 m Total Mass: 807,674 Kg Payload: 30,400 Kg

Stages: 2 1°Stage: 3 x RD-180 (LOX/RP-1) 2°Stage: 1 x J-2S (LOX/LH 2)

Launch Site: Cape Canaveral SLC-37B

“HL-42 Personnel & Logistics Vehicle”

Drawings are at the same scale

“HL-42 Personnel & Logistics Vehicle”

LEGEND 1. Launch 2. Max-Q phase 3. First stage jettison 4. LES Engines jettison 5. Second stage jettison 6. HL-42 in orbit

“HL-42 Personnel & Logistics Vehicle”

LEGEND 1. HL-42 prepares for re-entry 2. HL-42 performs the de-orbit burn 3. HL-42 uses thrusters to maneuver 4. HL-42 gain the correct attitude for re-entry 5. Atmosphere re-entry

“HL-42 Personnel & Logistics Vehicle”

LEGEND 1. Atmosphere entry 2. HL-42 takes the landing corridor 3. HL-42 gain the attitude for landing 4. HL-42 enters into the landing cone 5. HL-42 touchdown and landing

“HL-42 Personnel & Logistics Vehicle”

The conclusion of the Access to Space Option 3 team was that a single-stage-to-orbit (SSTO) vehicle was a feasible system that could achieve the ATS objectives and provide major life-cycle cost and performance benefits. NASA decided to proceed with Option 3 leading to three study contracts (Rockwell, McDonnell Douglas, Lockheed) for a suborbital, subscale demonstrator called X-33. In February, 2001 the Lockheed Martin X-33 demonstrator was cancelled due to technical issues including the test failure of a complex-shaped, composite hydrogen tank.

With the decision to proceed with ATS Option 3, work on the Option 2 architecture including the HL-42 effectively ended except for final documentation.

Could the HL-42 and new two-stage expendable vehicle have worked?

Technically, there is little to suggest otherwise. Life-cycle cost would have been the driving factor for an architecture that could have replaced the Space Shuttle in the years beyond 2005.

“HL-42 Personnel & Logistics Vehicle”