![]() Use dVp and dVi to reduce the Ang (from Map's second page - if you entered the target base on IMFD's main config page) to zero and the PeA to 65k. Then, just after entering the Earth's SOI, use IMFD Delta V program to perform a MCC. Just use periapsis mode (rather than re-entry mode), set the PeA to about 65k, and adjust the departure and arrival times to get the periapsis about 90 degrees west of the target. Only the ablative heatshields used on the Apollo missions were designed to handle the thermal load of a hyperbolic re-entry.Īs for the "magic number", LTMFD makes that obsolete. A better insulator, or some form of active cooling, would make inverted re-entries possible in Real Life.īTW, current heatshields such as the Shuttle's TPS wouldn't fare well with a re-entry profile that involves repeatedly entering and leaving the atmoshpere - the repeated heating/cooling cycle will fatigue the tiles (and the adhesive) and cause failures. The Shuttle's TPS, for instance, is "insulative", and is only effective for a limited time - after which the heat will have "soaked through" the insulation and into the vessels body and structure. In Real Life, inverted re-entries may not be possible with existing tech. Inverted re-entries allow you to stay in the atmosphere longer if you are coming in at hyperbolic velocities. Orientation relative to the Earth doesn't determine heating - orientation relative to the velocity vector does - so a 40 degree AoA is a 40 degree AoA no matter what your bank angle is.īank angle DOES affect your lift, and thus your VS. The idea that an inverted re-entry exposes the craft to different heat stresses is all in your imagination. In both cases, you will have a similar high AoA - so the exposed cross section is the same whether you are inverted or not. The first aerobrake gets me into MEO territory, the second down to about 1-2 Mm, then the third is easy peasy to get back into LEO, or if I have enough fuel, just skip the third aerobrake and burn to lower the apogee back down to 280-400km for LEO.įirst, the inverted re-entry doesn't expose the vessel to different heating than an "upright" re-entry. Using 60km and the very high AOA I was able to lower the apogee down to a managable height in three steps, which I think is the best one can hope for. Trying to go lower than that risks loss of vehicle. ![]() 60km for the perigee seems to be the magic number. ![]() Coming from the moon, I also don't have the fuel then to fire a retro grade burn to enter LEO before works great. I launch the XR-2 vertically using velcro rockets, dead stick the landings, since I do not have enough fuel otherwise. The XR-2 is already a fantasy machine to begin with, and I have set the config up to tone down that department, while still maintaining the flexibility the XR-2 provides, such as being able to land on the Moon. ![]() My issue is looking at the XR-2 re-enter the atmosphere this way, the first things I notice is that those huge bug-eye windows for the CDR and PLT are taking the brunt of the re-entry force and believing they would withstand that is just a bit too much to ask. The inverted re-entry with the XR-2, while fun to do, I see it as more of exploiting the code of the XR-2 and Orbiter to do something that otherwise cannot be done in the real world.īut you got the idea, the lift from the wings is reversed so while the effect of hitting the atmosphere that fast will want to throw the ship back out into space, flying the XR-2 inverted will allow the pilot to control the AoA and actually cancel out that force and allow you to plow through the upper levels of the atmosphere for a very extended period of time as you slowly get speed down to LEO levels, at which you can flip the ship over and re-enter as normal. ![]()
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