Bluestar

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Bluestar has a long and varied history since I first started studying it in April 2001 (before Columbia's accident and the founding of After Columbia.) Initially, it was very similar to Saenger II, or David Ashford's Spacebus (http://www.bristolspaceplanes.com/projects/spacebus.shtml). That concept is dead because it is very difficult to accomplish. SSTO was never considered

As the concept evolved (off and on since 2001), it has slowly grown more ballistic, from the top down. The booster is still the same type of booster as the original concept, but it might yet be replaced by a stack of Lilmax modules (which are reusable.) A number of options have been looked at for the orbiter:

Shuttle-type orbiter: This had an HL-10 lifting body shape, dorsal payload bay, landng gear, and was very much like a Phase A Shuttle Orbiter. After looking at the Phase A and Phase B Shuttle designs critically, I realized that the required mass fraction for this orbiter could not be met, unless at extreme expense. I started to look for ways to cut down on mass.

Lifting Body Pond Lander: This running baseline is still "official", but is probably on its way out. The orbiter lacks a landing gear, but still retains the same type of payload bay as before, as well as a lifting body shape. For this craft, the lifting body provides lift only for the entry phase, and the craft deploys a parasol much like X-38's once it is subsonic. After this, it flies to a landing in a freshwater pond, where it is towed to dockside and lifted from the water using a crane. It also has better contingency options, being able to splashdown at sea or on land. The latter case would be preferable for the crew on board (assuming there is a crew on board, this is increasingly unlikely), since the orbiter will not be very seaworthy in any case.

Lilmax Bluestar: This takes a pure ballistic approach to full reusability. Details about Lilmax lower stage reusability are on the Lilmax page. This orbiter is based around a biconic fairing, and would therefore have some crossrange, but nowhere near as much as the Shuttle. To enable a once around abort landing, it would need to launch due east from a tropical site, and polar missions would be restricted to high latitudes. The orbiter replaces the normally expendable upper stage of Lilmax: -- The Lilmax portion of the ascent is highly conventional, except that the boosters have parachutes and can be recovered and reused. -- The arrangement of the orbiter, at first, is conventional, except that the fairing is a single piece. The payload is inside the fairing, and the entire upper stage is behind it. -- At staging, the orbiter extends its main nozzle and lights its main engines. It has pressure-fed verniers similar to those on the expendable Lilmax upper stage. -- The most obvious variation from a normal expendable initially is that the fairing is retained to orbit. -- Once on orbit, the fairing is disengaged from its forward attaching plane and extended forward on a telescoping boom until it is clear of the payload. -- Once clear, the fairing is able to pivot laterally about its telescopic joint on the upper stage. Getting the fairing out of the way like this eliminates lateral payload integration, and makes it so that the payload can deport forward like it does on any expendable. -- The payload is separated, the customer cheers, goes to the nearest pub and gets obliterated. -- Once the payload is clear and the orbiter well separated from it, there are a couple of options to button up things for entry. -- Forward fairing stowage. The fairing is rotated back to the forward position, the nozzle extension retracted, and the fairing is translated back well past its ascent position until the whole upper stage is inside it. In this configuration, it enters and lands much like the Pond Lander. -- Aft fairing stowage. The telescopic extension rotates the fairing until it is entirely behind the upper stage. Once there, the nozzle is retracted, along with the fairing itself, enclosing the upper stage in the position backwards relative to the fairing. It enters the fairing nose first (upper stage "backwards") and then lands much like the Pond Lander.

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