XR2 rentery corridor tips

[J_Aerospace]

HI there first of all i love this addon it really sets the standard.
BUt i have been trying to do a rentry but keep either overshotting the landing zone or just burn up does anyone have any tips?

 

[streb2001]

First obvious tip: dump all of your scram and main fuel.

 

[RisingFury]

Use the AeroBreakMFD. And make sure your slope doesn't exceed 1°.

 

[Genius]

Try use autofcs. Switch to manual mode when near the base you want to land. Or wait untill it line up with the runway "using AFCS". Then disengage AFCS and use the autoland feature of the ship.
Good luck

 

[J_Aerospace]

Thanks that great.
Is there a preferd AOA for rentery in the xr2 when is the best time to do a retro burn and for how long?

 

[streb2001]

Deorbit at about 18,000km from base ie. almost diametrically opposite and reduce periapsis to about 30km altitude. Between 40 and 45 AoA at interface.

 

[Peskie]

I use IMFD5.1 (http://koti.mbnet.fi/jarmonik/Orbiter.html) in BaseApproach->Reentry mode. For the XR series I've used Alt=80km, ReA=1.2, Ant=30 with success from LEO. I've also set Ant (the reentry anticipation angle) as high as 60 or so and streatched the glide out.

If you're coming from a higher/hyberbolic orbit where IMFD gives too high a reentry velocity (ReV) you'll either want to enter an orbit first (can also be done with BaseApproach->OrbitInsert or adjust the paramaters to allow you time to do an aero capture/brake before starting the reentry proper.

I've done aero captures with the XR2 but since the built in autopilot doesn't allow for a bank of 180 (i.e. inverted so you can use your lift to hold you in the upper atmosphere long enough to slow down enough) it can be tougher than it should be.

 

[tl8]

There is a playback here: http://orbiter.dansteph.com/forum/read.php?f=3&i=60863&t=60863

 

[Omhra]

Amazing... man... Just amazing. Spent the night at ISS... starting descent to Cape.


-----Posted Added-----


With 20% scram and 20% main fuel I lowered my orbit to 150km A.S.L. Then, being aligned with base, in diametric opposition with base I lowered PeA to 50km A.S.L. Attitude was around 50 degrees nose up and gradually dropped, as needed, to hold a good descent rate of 120ms until temperature approached the red and then shallow attitude to loose down vector. Once heat dissipated enough I nosed-up again and repeated the cycle with a bank of up to 60 degrees one way and then the other to loose speed to around 5000ms at 40km ASL.
finally crossed the gulf at 3000ms at 35km ASL at shallow AOA of 15 degrees or so when I engaged wind brakes... with the peninsula in sight and around 2500ms I disengaged brakes and started a descent of 20 degrees. At the 25km ASL point I engaged brakes to reduce speed for that last wallop of atmosphere at 20km ASL...
Then with brakes disengaged did a south turn followed with a 180 turn to align with the runway 30 degrees down from me. After a few moments I dropped gear and engaged brakes for the last time. Nice smooth touch down.
This is a beautiful model all around. looks and behaves very nice.
I should say that I lost 2 ships while in training for this mission. But the mission itself was exiting and successful.

 

[WombatControl]

I use the BaseSync MFD. It took some trial and error, but I've found that a descent from ISS altitude seems to work with an reentry angle of 0.8, a reentry anticipation of 10 degrees and a reference altitude of 20km. Following the MFD puts you right on path to the Cape without being too far off target and without heating problems. Setting the AOA to 40 degrees in the Attitude Control autopilot seems to work fine in terms of putting you on the right trajectory.

 

[Peskie]

reference altitude

I use the BaseSync MFD. It took some trial and error, but I've found that a descent from ISS altitude seems to work with an reentry angle of 0.8, a reentry anticipation of 10 degrees and a reference altitude of 20km.

You can use whatever works for you ... but using a reference altitude of 20km for the Earth is silly. The numbers matter at entry interface, which for Earth from LEO is usually somewhere between ~72km and ~80km. Reentry MFD will tell you the actual interface altitude and time to interface on your current trajectory.

Both Interplanetary MFD and BaseSync MFD only have inputs for reference alt, reentry angle, and anticipation angle. At least Interplanetary MFD tells you the other important value, reentry speed (at reference altitude) which is also needed to tune the reentry parameters. E.g. the numbers you use for an XR2 from LEO won't work for an XR2 coming from Mars because you're coming in a lot faster.

 

[J_Aerospace]

is there an english version of this http://orbiter.dansteph.com/forum/read.php?f=3&i=60863&t=60863
bablefish will not translate it correctly

 

[Dr Nick]

I use IMFD5.1 (http://koti.mbnet.fi/jarmonik/Orbiter.html) in BaseApproach->Reentry mode. For the XR series I've used Alt=80km, ReA=1.2, Ant=30 with success from LEO. I've also set Ant (the reentry anticipation angle) as high as 60 or so and streatched the glide out.

Is there a way to use IMFD when you're already in earth orbit to set up those parameters?

I've tried and the burn values are crazy (it wants a delta V of 12k m/s or something similar).

 

[Jer95]

I have made a chart of earth reentery
If you deorbit at 100 mile alt and 8000 miles to base, at the right time, you will see this, at 40 aoa 50 and 30

 

[V8Li]

Get the Reentry MFD ( http://www.orbitermars.co.uk/ ).
It's basic, it gives you the required deceleration to hit the base and some graphics to know when you're on the right path (and when to bank). It's all you need, reentry is (imho) the most flexible part of a fligh and the hardest to understand, if you decelerate too fast all you have to do is stay longer in the upper atmosphere and get closer to base. A little practice is all you need at first but you'll never miss a reentry.

 

[Sky Captain]

When coming home from ISS I usually do a retro burn ~ 6000 - 7000 km from base and have a nice fast reentry with hull temps hitting red.

 

[T.Neo]

I'd also advise dumping all SCRAM fuel, but leave 10-15% main fuel in case you come in short.

 

[Jer95]

When coming home from ISS I usually do a retro burn ~ 6000 - 7000 km from base and have a nice fast reentry with hull temps hitting red.

I deorbit when its like 7000 miles to base

 

[NukeET]

I'd also advise dumping all SCRAM fuel, but leave 10-15% main fuel in case you come in short.

Or long.