KerbalX

Description

40t to 100k circ
Deorbit burn at 136deg1’ to 40k periapse

A stock rocket called booster 40t reuseable. Built with 101 of the finest parts, its root part is probeStackLarge.

Built in the VAB in KSP version 1.5.1.

Details

• Type: VAB
• Class: lifter
• Part Count: 101
• Pure Stock

Will lift 40 tonnes to a circular 100km orbit. Booster is equipped to remain in orbit for later deorbit at your convenience. Net cost after recovery is about $40k, yielding $1k/ton to place a full-sized payload in orbit.

Lands via suicide burn. (No paracutes.) Recommend you add mechjeb or similar for the suicide burn. Terminal velocity is low (below 300 m/s I think) but the booster has high TWR.

The re-entry relies on the absurd current parameters of a stock part: heavy airplane landing gear. This gear is able to survive exposure to high heat – rubber tires and all – while providing high drag, and also has the extreme strength that is great when landing a heavy booster. The airbrakes serve to balance the drag, else the booster would flip to prograde. (I probably could have used more landing gear in place of the airbrakes, lowering part count, but I couldn’t stomach that look.)

Landing method:
From the 100km orbit, you need to drop your periapse to 40km at a specific longitude: 136 degrees 10 minutes East. This is a small retro-burn, about 50 m/s.

Here’s the way I do it. Is there an easier way? While in 100km orbit, prepare by setting the autopilot to retrograde at about 120 East longitude. In mechjeb manuever planner, prepare to set periapse to 40km with immediate execution (but do not execute yet). At 136 degrees 10 minutes East longitude, press the create&execute button on the manuever planner. (Because the booster was oriented retrograde, the maneuver will instantly fire.)

Deploy brakes and gear while still in orbit. Warp in, oriented retrograde. The airbrakes will get hot, but not too hot. The 136 1'E retro-burn will have you slightly overshooting KSC. As you are overhead KSC and overshooting, burn some more (typically 200m/s retro or so) until you will land at KSC rather than offshore. (The red landing circle of KER is helpful.) When the expected landing point looks good, ask Mechjeb Landing stuff to Land Somewhere. This will cue up a suicide burn. Landing is very solid, very forgiving.

I’m able to consistently get above 97% recovery, yielding a net cost for the boost of about $40k.