News The Space Shuttle for Flightgear 3.6

Thorsten

New member
Joined
Dec 7, 2013
Messages
737
Reaction score
1
Points
0
Another development cycle closes, and I'm proceeding to milestone testing - which means plenty of pretty views.


Shuttle meets ISS - a relatively fast dusk flyaround maneuver. Orbital DAP to free, establish a constant pitch rotation of 0.4 deg/s, use THC in NORM to keep ISS centered in COAS view, use radar ranging to manage the distance and conpensate for centrifugal force, and we're slowly going around the station.

Actually it's a fairly busy maneuver at that speed...



Look at those clouds!



The station seen through the COAS recticle.



Last sunlight seen through the overhead windows.



And, as we rotate around, the lights of Paris above - or below, dependent on how your coordinate system is arranged :)

 

Wolf

Donator
Donator
Joined
Feb 10, 2008
Messages
1,083
Reaction score
2
Points
38
Location
Milan
Another development cycle closes, and I'm proceeding to milestone testing - which means plenty of pretty views.


Shuttle meets ISS - a relatively fast dusk flyaround maneuver. Orbital DAP to free, establish a constant pitch rotation of 0.4 deg/s, use THC in NORM to keep ISS centered in COAS view, use radar ranging to manage the distance and conpensate for centrifugal force, and we're slowly going around the station.

Actually it's a fairly busy maneuver at that speed...



Look at those clouds!



The station seen through the COAS recticle.



Last sunlight seen through the overhead windows.



And, as we rotate around, the lights of Paris above - or below, dependent on how your coordinate system is arranged :)



Are you considering implementing an RPOP tool (like the one they used on their onboard laptop computer)? We had it for Orbiter 2010 (unfortunately it doesn't work with O2016) and it was a great aid in flying and monitoring precise proximity operations and flyarounds (plus the extra realism added)
 

Thorsten

New member
Joined
Dec 7, 2013
Messages
737
Reaction score
1
Points
0
Are you considering implementing an RPOP tool (like the one they used on their onboard laptop computer)?

I'm not familiar with the tool (basically I'm still reading my way into the more intricate parts of Rendezvous literature...) - but based on past experience, if someone is interested in a system, the system has really flown (or was planned to fly), there's sufficient documentation and an implementation is possible, I try to get it into the sim.

it's how we got the OMS kit and OMS assist burn capability after all...
 

Thorsten

New member
Joined
Dec 7, 2013
Messages
737
Reaction score
1
Points
0
Some more impressions from testing various scenarios:

Antarctica from a 730 x 640 nm orbit - made possible by lugging the 1500 fps variant of the OMS kit into orbit and sitting through 8 minute long OMS-1 and OMS-2 burns. Kit is dry at this point, but the remaining propellant should be more than enough to de-orbit - it might be prudent to do an aerobraking pass to lower apoapsis before the final entry though... Admittedly I have little flight experience with such high orbits, but the view surely is great.





Aw, that sucks. Second engine fails in a droop guidance test.

Droop guidance actually worked fine, but I messed up royally - first I forgot to switch the good engine to 109% power and lost precious propellant and altitude before I remembered, then as a result MECO was a messy affair with residual rotation - and rather than wait for the system to do a proper ET-Sep, I should have forced it early on - not doing so cost me another few precious seconds. The biggest mistake then was to transit to MM 301 too early - which in a TAL automatically forwards to 304 and switches Aerojet DAP on - which is a pretty poor tool at acquire a good entry attitude.

By the time I had corrected that, I was already too deep in the atmosphere for the RCS to get me to a good attitude and I burned up.

Well - better keep them cue cards handy, procedure is there for something...




Second abort scenario tested was a single engine TAL to LeTube - that worked rather well (probably because this time I did remember proper procedure...)

Passing the coast of Spain



Over Southern France on the HAC



... and down on the ground - coming right out of the HAC there was cloud cover with rain underneath - TACAN nav accuracy and poor visibility do not add up to a comfortable combination - in fact I over-ran the runway somewhat (off into the green with ~ 40 kt) - I suppose in reality some gear damage would have been the result.

 

Thorsten

New member
Joined
Dec 7, 2013
Messages
737
Reaction score
1
Points
0
The new version of the Space Shuttle Flight Manual (both Standard and Deluxe edition) referring to milestone 11 is out (259 pages for the deluxe edition.)!



Please download and enjoy the version of your choice! Plenty of news on COAS, OMS kit, rendezvous and proximity operations, new dialogs,...
 

Gingin

Member
Joined
Feb 5, 2015
Messages
256
Reaction score
4
Points
18
Location
City of Light
A sum up of my last test sessions.

High Energy TAL to Gander.
An Exotic TAL that would have been useful in case of a triple engine failure between 20 and 22000 fps of inertial Speed for a Launch to ISS ( 51.6 ° of Inc)

Procedure developped in the 2000's .
At those speeds, too much velocity for a normal Gander TAL and not enough speed for a TAL to Shannon once Ocean was crossed.
Really exotic and smart one.

The checklist menu




And the sum up


https://forum.flightgear.org/viewtopic.php?f=19&t=35763
 

Thorsten

New member
Joined
Dec 7, 2013
Messages
737
Reaction score
1
Points
0
In case you were wondering - development is still happening:)

Currently I'm busy to enable the cue card binders to be usable in the cockpit - right now you can attach some systems procedure binders to the velcro and browse through them - because that might be awkward in a stress situation, each page can pop up in a separate window when clicking on it.



Otherwise I've done some basic stuff (which Orbiter had for ages, but I had to code from scratch) - management routines for grabbing payloads from space (this alters the number of objects to be simulated...) and for things like assemby - so now we can grab a satellite and return it to Earth.

Thanks to Waybe Bragg, we also now have the Hubble Space Telescope as a (challenging) rendezvous target (unless you bring the OMS Kit of course...).

And for training purposes, I've added a scenario overlay which allows to quickly jump to specific tasks - using a scenario overlay, one can for instance set Shuttle and rendezvous to specific positions, or set a Shuttle internal state (failures...) or such like - that's kind f orthogonal to saving/resuming a state as one would do when simulating a mission in real time.
 

Thorsten

New member
Joined
Dec 7, 2013
Messages
737
Reaction score
1
Points
0
Finally getting the CAM matrix voting problem under control - here's GPC 2 after failing to sync with the redundant set (on orbit here being composed of 1-3) in step 2 - in step 1 it votes against 1 and 3, but then in step 2 the algorithm decides that as a minority being voted out, it can't vote against others any more, so it indicates self-fail.



Okay, this is a pretty exotic part of Shuttle operations... but we now have it anyway.
 

Thorsten

New member
Joined
Dec 7, 2013
Messages
737
Reaction score
1
Points
0
A genuinely different perspective for a change. In reality, the Shuttle has often been escorted by fighter jets in its last flight phase - so I've wondered how it looks from the cockpit of such a jet.

To re-create the experience, I recorded a Shuttle TAEM trajectory to Edwards AFB, fed that to the AI system of FG, got myself into the cockpit of an F16 and tried to intercept the incoming spacecraft.

It turns out to be a really difficult maneuver - for an early intercept the F-16 needs to climb high and hit full AB, but quickly switch into full brake mode because it's simply not meant to descent at 7000 ft/min, so it's a bit hard not to overshoot the Shuttle, basically engine idle and full spoilers do the job

From the Shuttle cockpit, TAEM is a sedate affair - nothing much happens, lots of straight-line flight while one has a chance to look at the NAV filters and does a few last minute weather adjustments. Also, it feels pretty slow going after the entry phase. From the F-16, it feels nothing like that, it's a hectic scramble to intercept followed by a completely mad spiral dive.

In formation just before HAC:



...and during HAC



Good radar lock as the Shuttle dives into final approach:

 

Thorsten

New member
Joined
Dec 7, 2013
Messages
737
Reaction score
1
Points
0
I'm happy to announce that the next milestone of the Shuttle is tagged and will soon be widely available via the standard FG download option.

There's quite some work under the hood, but the big new thing is the option to grapple payloads (or push them away if you're not careful...). Also, there's now the concept of a 'Scenario' which quickly gets one into an interesting mission phase, and there's support to velcro cue cards in-sim into their positions.

Here's some impressions of the pre-milestone tests I've done:

Fuel dump during an RTLS:



ET separation and pitchup before Nz-holding phase:



Alpha transition (in the event, I was high on energy so I got to experience S-turns later):



Night portion of the orbit, after TI burn in transit to ISS:



ISS in view:



Approaching a satellite for capture:



Stationkeeping in capture position:



And... grabbed in the first attempt:



View from the payload specialist station:



Off into the sunset...

 

Thorsten

New member
Joined
Dec 7, 2013
Messages
737
Reaction score
1
Points
0
The new version of the Space Shuttle Flight Manual (both Standard and Deluxe edition) referring to milestone 12 is out!



Please download and enjoy the version of your choice!

The milestone itself is now also available via the standard FG download.

***

Since then, I've been busy going through the details of the MPS workbook and implementing them in the devel version - so that's a preview of what is to come for the next milestone. The various ascent failure scenarios are now supported in quite some detail, we're going to have data and command path failures, PASS and BFS specific CWS messages, red-lined engines which are dangerous to run, isolatable and non-isolatable leaks in the Helium system, failures of the cutoff switches or the ET sep switch and their software alternatives,... Basically a lot of the original procedures should now be fully doable (with meaningful steps).

I've also added an ascent failure trainer that presents a random fault scenario in three difficulty levels (the highest difficulty may not always be survivable - there's 3EO possible and that doesn't always end well...) - so one can specifically train diagnostics and fault response during ascent.
 

Gingin

Member
Joined
Feb 5, 2015
Messages
256
Reaction score
4
Points
18
Location
City of Light
Top