The LP1 is a medium first stage reusable launch vehicle. Upon jettisoning the LP1 stage, the progress of the launch is placed on hold while the player attempts to land the LP1 onto the landing pad. After this phase is completed (successful or not), the launch resumes and the player continues with trying to get the payload to orbit.
NOTE: The awarding of the Quick Launch or refund happens immediately after a successful landing, and is not dependent upon the payload successfully reaching orbit.
- Unlike conventional non-reusable rockets, the engines of the LP1 can be ignited as late as when the Countdown Clock reaches zero and the LP1 is falling after the Tower Support Arms release it.
- During launch, the outer left & right engines seem to function as boosters. If the LP1 is separated too early, it has been reported that they may (but not always) continue to burn until they exhaust their fuel supply, irregardless as to whether the player is pressing the thrust button or not.
- You can accumulate Quick Launches rapidly by repeatedly launching the LP1 or the Eagle 8 First Stage carrying nothing and landing them.
- After the LP1 separates from the Payload stage and is attempting to return to its landing pad, the "Destruct" button does not appear should it become inverted during flight. The player must either correct the rocket's position back to vertical, or let it crash.
- Prior to update 1.7.1, the landing pad was previously labeled "LP1".
- The LP1 was succeeded by the Eagle 8, much like the Falcon 9 did the Grasshopper test vehicle, to which the LP has been compared.
- The LP1 can only successfully land on the designated pad. Landing in any other location will result in failure, and the rocket will explode. Probably this is because of dust accumulation on the engines, which end up in malfunction.