The Sun Rides A Workhorse
The Delta was the fourth configuration of te Thor-Able launch vehicle. Not part of the mannedspace program, this rocket never archieved the fame of the Redstone, Atlas or Saturn. Yet, in all its 34 versions, the Delta has been the workhorse of America's exploration of the world beyond out own. Its exceptional reliability made it the launch vehicle of choice for many of the most significant breakthroughs of our time.
When it launched the Deep Space Probe, Pioneer 5, on March 11, 1960, the beach ball-sized spacecraft was equipped with four paddle like solar cells that rechargedthe on-board batteries that provided electrical power. Invented in 1941 by American Russell Ohl, improved solar cells have become a reliable source of electrical power for satellites and the International Space Station.
ROCKET DATA: Delta
Height: 27 meters (89.3 feet)
Diameter: 2.24 meters (88.9 inches)
First stage propellants: Liquid Oxygen (LOX) and kerosene
Second and Thrid stage propellants: Solid
Lift-off thrust: 152,000 pounds
From: Wikipedia
Delta
Delta is a family of expendable launch systems that have provided space launch capability in the United States since 1960. There have been over 300 Delta rockets launched, with a 95% success rate. Two Delta launch systems – Delta II and Delta IV – are in active use. Delta rockets are currently manufactured and launched by the United Launch Alliance.
Delta origins
Main article: Thor (rocket family)
The original Delta rockets used a modified version of the PGM-17 Thor, the first ballistic missile deployed by the United States, as their first stage. The Thor had been designed in the mid-'50s to reach Moscow from bases in Britain or similar allied nations, and the first wholly successful Thor launch had occurred in September 1957. Subsequent satellite and space probe flights soon followed, using a Thor first stage with several different upper stages. The fourth upper stage used on the Thor was the Thor "Delta," delta being the fourth letter of the Greek alphabet. Eventually the entire Thor-Delta launch vehicle came to be called simply, "Delta."
NASA intended Delta as "an interim general purpose vehicle" to be "used for communication, meteorological, and scientific satellites and lunar probes during '60 and '61". The plan was to replace Delta with other rocket designs when they came on-line. The Delta design emphasized reliability rather than performance by replacing components which had caused problems on earlier Thor flights. NASA let the original Delta contract to the Douglas Aircraft Company in April 1959 for 12 vehicles of this design:
Stage 1: Modified Thor IRBM with a Block I MB-3 engine producing 152,000 lbf (680 kN) thrust. (LOX/RP1 turbopump, gimbal mounted engine, two verniers for roll control)
Stage 2: Modified Able. Pressure fed UDMH/nitric acid powered Aerojet AJ-10-118 engine producing 7,700 lbf (34 kN). This reliable engine cost $4 million to build and is still flying in modified form today. Gas jet attitude control system.
Stage 3: Altair. A spin stabilized (via a turntable on top of the Able) at 100 rpm by two solid rocket motors before separation. One ABL X-248 solid rocket motor provided 2,800 lbf (12 kN) of thrust for 28 seconds. The stage weighed 500 pounds (230 kg) and was largely constructed of wound fiberglass.
These vehicles would be able to place 650 pounds (290 kg) into a 150 to 230 miles (240 to 370 km) LEO or 100 pounds (45 kg) into GTO. Eleven of the twelve initial Delta flights were successful. The total project development and launch cost came to $43 million, $3 million over budget. An order for 14 more vehicles was let before 1962.