Can someone please help me with my first space plane (Details in the main text)
So it's my first ever attempt at making a space plane reaching the orbit, it managed to do that but it is highly inefficient for only 2 small cargo fuselages of space putting them into 80km orbit with barely any fuel left to spare for deorbiting.
Here is the staging and flight plan breakdown:
1 Launch: I launch it from the runway, it is barely able to gain enough speed to take off, then I coast around 20 seconds with 0-10 v/s while gaining speed to 240m/s+ (TWR 0.76)
2 First tilt: After gaining enough speed I tilt it up at around 40-60 degrees to exit thick layers of the atmosphere quickly with low speed (TWR 0.96-1.24)
3 Second tilt: After exiting the thickest part of the atmosphere and entering the middle part I tilt it to 20 degrees keeping the v/s at around 100 (TWR 1.70)
4 Fuel stage separation and recovery(The huge gray pencil on top): after it burns through the main fuel stage it separates using solid motors to then coast down to 25km and open its parachutes (Twr shoots up after staging so I need to power down to TWR:2.0 while stage TWR is: 2.74)
5 Keep burning till the apoapsis is 80+km, I usually pitch the plane up and put it into prograde after it starts to burn in the remaining atmosphere during altitude gain because of the speed around 1800m/s (TWR 3.2 but I keep it after 2.0)
6 Coast to apoapsis: Coast to the 80km then burn to finish the orbit praying that there is going to be enough fuel left, opening the bay, putting the payload into orbit, closing it and preparing for reentry (TWR 3.4)
7 Re-entry: I re-enter at 40 degrees but end up spinning out in the thicker parts of the atmosphere doing a cobra, it works to speed down quickly(1900m/s to like 500m/s until I am able to stabilise it and all in 5s, very nice slow down but my kerbals don't enjoy tanking 10g's), but it's not planned even in the slightest, I implemented air brakes further to the back instead of being near the COM of the plane without the fuel tank, but I haven't tested them yet, when it atmosphere at around 300m/s I activate the jet stage (two tiny Juno engines supplied by tiny jet tanks) I fly to the KSC where I simply land and stage the drogue parachutes, that's all we are home only held together by hopes and prayers, it somehow enters orbit every time but it's extremely scary and inefficient