Columbia, go TAL Abort

[Gingin]

Good evening,

I am still discovering SSU. Today, I am gonna try another kind of Abort.
After RTLS ( http://www.orbiter-forum.com/showthread.php?t=38313), really tight and complicated with timing, I decided to try some TAL abort to Istres, a beautiful french airport with 5km of concrete :thumbup:


The window for this abort with one engine less (2 ENG TAL) opens quite early in the flight, around 2mn30 (Vi around 5700fps). It varies depending on TAL site and orbiter weight

Some generic sum up of different kind of abort

Let's go guys.

Nice and easy lift off, always tremendous view for the Go Pro ahah

SRB separation

Engine failure around 2mn40. Vi around 5700 fps, just on the edge. It's gonna be challenging during entry phase energy wise

Main aim is now to be at MECO around Mach 24, between 360 and 380 kf, around 2500Nm from Istres with an offset of maximum 500Nm (the least the best)
On the cue card below, good speed at MECO for FNI is between 23,5 and 24,5

I will cheat a bit and use Base Sync to monitor the offset.
Initally, heading around 40° and pitch of 50° to reach 380 kft

Bye bye Florida, hello Ocean.

Voilà, we reached 380 kft. Now, we gonna play with pitch and vertical velocity to stay between 360 and 380 kft. We are at our apogee and we don't want to go down too fast into atmosphere before MECO.
Our path tendency, shows by yellow dot is very helpfull to manage vertical acceleration

Around Vi=14000kft, Roll To Head Up to be in good position for ET separation.

MECO time, M23 and 360kft

Altitude is Ok, Speed a bit low. ( I put the failure a bit too early actually. EO Vi should have been 6200 instead of 5700 like on the cue card below)
We are just in the low energy area, nothing to worry about too much. I am gonna delay Roll Reversal to have a maximum of Lift during first stage of entry

Very short time before entry, time for LO2, LH2 dump and ET doors closure

We are now at entry interface. 2800Nm, 360kft, M22,2.
Still low on energy. Hopefully, Delta Az is very low. I barely have offset with Istres so I can delay Roll Reversal and come back on path during entry ( well, I hope at least )
If I would have been low on speed and with a high lateral offset, it would have been really really tight.

Burning like hell !!

Coming back nicely on path

200kft, Entry traj 2, still a bit low. No roll reversal

Here we are, on path, and even a bit high now ahah

Ok, time for roll reversal now and to increase vertical speed

 

[Gingin]

Do you recognize the coast? It's near Bordeaux, wine's capital of the world

We are a bit hight now. I don't want to be too harsh with S-turn.
I am gonna change runway and take 33 instead of 15 for extra miles.
ITEM 3 EXE on CRT 1. It's in the box, and path is a bit better.

Pyrenees in sight

Yeah, Istres in sight. I have to install Earth HD texture.

HAC closing in, some S turns to manage energy.

In the HAC, 270° by the right, 37000 feet. "Columbia, you are looking good"

Out of the HAC, on glide ,a bit left of the loc.
Two runways? Weird, it might be a glitch with an add on I installed for Istres enhancement.

Short final and pre flare

And touch, welcome in France Columbia

Nice challenge to do. Really love SSU and all the opportunities ahead.
As usual, using official docs and numbers work pretty well in that sim, nice nice nice

 

[GLS]

SSU's runway looks like the one with the overrun/underrun. The other is probably from some addon you have installed.

 

[Wolf]

Gingin, you re really doing a great job with SSU!
I was able to install it in Orbiter2016 today and just tried to simulate an engine failure by shutting down one SSME, then from right seat (PLT side) I tried to get manual throttle control but it did not work... I kept pressing the SPDBK/THR pushbutton by with no luck.
How do you actually do that?

 

[Gingin]

Hey Wolf, Thanks.
There is a push button on the thrust/speed brake lever you have to push
With my Azerty keyboard, I am pressing the touch which is doing that )
It's one touch right to the 0 not on the numpad.
Then it should move from Auto to Man

 

[Wolf]

Hey Wolf, Thanks.
There is a push button on the thrust/speed brake lever you have to push
With my Azerty keyboard, I am pressing the touch which is doing that )
It's one touch right to the 0 not on the numpad.
Then it should move from Auto to Man

Sorry I m not quite sure I understand: Is there a pushbutton on the thrust/spdbrake lever itself? I thought I had to press and hold the SPBK/THC pushbutton located just beside the AUTO/MAN Pitch and Roll pushbuttons.
Are you using a specific button on your keyboard to do that? Which one?
Sorry, I sm a bit confused..

 

[GLS]

Sorry I m not quite sure I understand: Is there a pushbutton on the thrust/spdbrake lever itself? I thought I had to press and hold the SPBK/THC pushbutton located just beside the AUTO/MAN Pitch and Roll pushbuttons.
Are you using a specific button on your keyboard to do that? Which one?
Sorry, I sm a bit confused..

Please look in the manual, I think I explained it well enough there.

 

[Gingin]

Yes , there is a push button on the thrust lever itself. We can't press it in the game, that's why it was coded on the keyboard.

To take manual control, im going Pilot side and pressing on my keyboard this touch: )
It's located right from the zero touch ( the zero on top of the keyboard, not from numpad)

 

[Wolf]

Yes , there is a push button on the thrust lever itself. We can't press it in the game, that's why it was coded on the keyboard.

To take manual control, im going Pilot side and pressing on my keyboard this touch: )
It's located right from the zero touch ( the zero on top of the keyboard, not from numpad)

I see. Thanks a lot for the help

 

[Wolf]

Ok, this is what happens on my side:when I try to get manual throttle control during launch, keeping the correct button on my keyboard pressed let me gain manual control but two things happen:
1) there is no way to actually change the actual thrust setting (either by using my joystick thrust lever or via the Orbiter remote control window. No matter what change I make the thrust on the SSME stays the same (in my case 100%)

2) If I release the keyboard button (even after a prolonged time) thust control immediately reverts to AUTO.

I read you had the same problem if you modify the thrust range limits in the SSU cfg file in order to get the extra thust you need for RTLS (109%) but I haven't changed anything.
Simply I am not able to manually control the SSME thrust...

Any suggestion?

 

[Gingin]

Once in manual control, press + or - minus on the numpad.

In'the config file, if you put thrust above 106%, manual mode will not work.
Max thrust in manual is104%
It should be more than enough for RTLS.
Normally for two engine rtls, outbound legs is 104% inbound 100% and during PPD you reduce gradually to 68%

 

[Wolf]

Once in manual control, press + or - minus on the numpad.

In'the config file, if you put thrust above 106%, manual mode will not work.
Max thrust in manual is104%
It should be more than enough for RTLS.
Normally for two engine rtls, outbound legs is 104% inbound 100% and during PPD you reduce gradually to 68%

Ok thanks a lot for your help. I was missing the +/- numpad inputs... it is actually in the SSU manual..
Don't mean to bother you but I have one more question: have you ever experienced any problems during the TAL scenario after ET SEP when you switch to MM304? I always have a CTD when passing from MM302 to MM303 (do not have this issue in the RTLS case). Or maybe there is a way to transition directly from MM104 (after ET SEP) to MM304...
What I do in sequence is: after ET SEP (MM104) in order to pop up MM304 I select MM301, then 302, 303 and finally 304. Trying to skip them and inputting MM304 directly triggers an "illegal entry"...

 

[Gingin]

I don't have CTD.

I ussually cycle through all MM

After ET, you are in MM 104.
I do MM105,106
Then MM201
Finally, MM301,302,303 and 304

I don't know if you can directly switch from OPS 1 (MM104) to OPS 3 (MM301)

 

[Thorsten]

At least in reality you can (in fact, when TAL is selected in OPS 1 typing

OPS 301 PRO

brings you directly into MM 304 (admittedly I haven't implemented that one myself).

 

[DaveS]

None of the abort modes have been implemented at all in SSU, so proper DPS functionality isn't there.

 

[Wolf]

I don't have CTD.

I ussually cycle through all MM

After ET, you are in MM 104.
I do MM105,106
Then MM201
Finally, MM301,302,303 and 304

I don't know if you can directly switch from OPS 1 (MM104) to OPS 3 (MM301)

You should be able to go directly to MM301 after ET SEP (when MM automatically transfers to 104) so you can skip 105/106/201
It is strange though that when I cicle through the modes as soon as I transition from MM302 to 303 the sim crashes... could it be a D3D9 issue?

This is the error message I get (and it happens also running D3D7)

 

[GLS]

You should be able to go directly to MM301 after ET SEP (when MM automatically transfers to 104) so you can skip 105/106/201
It is strange though that when I cicle through the modes as soon as I transition from MM302 to 303 the sim crashes... could it be a D3D9 issue?

This is the error message I get (and it happens also running D3D7)
View attachment 15209

That appears to me sometimes, and although I never checked it I'd say it is related to the current trajectory of the vehicle and the selected landing site. I usually press ignore twice and it keeps running without crashing.

 

[Thorsten]

Is the cloudy structure at the upper edge of the plasma cone a nose module right thruster firing?

 

[GLS]

Is the cloudy structure at the upper edge of the plasma cone a nose module right thruster firing?

FRCS firing. :facepalm:
Currently we don't have neither the RCS nor the GPC setup to fire specific RCS jets. :shrug:

 

[Thorsten]

On the danger of telling something you know already - the whole forward RCS module isn't used at all by the Aerojet DAP (my understanding is that nominally the propellant gets dumped before entry for security reasons).