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Hi
The same as for 2010
The same as for 2010
OHM Launch MFD - v. 1.6.6 for Orbiter 2016
- Thread starter OrbitHangar
- Start date
Is there somewhere a detailed procedure, how to use the direct ascent AP, so it might work more reliable ?
I mean, I got some successfull results, but the target offsets were allways wrong...sometimes 10 kms sometimes...more than 800 kms.
I got also plenty of complete screwed-up launches.
In all tests, I am using the same starting scenario:
In the XR2 folder : "1 - Ready for takeoff to ISS".
I know, when the scenario loads-up, it's allready to late to start the direct-ascent, so I waited then to the next (ascending/42 degrees launch heading) node.
I started at at about 1000 seconds before the ISS would overfly my lauch position.
(I tested also different timings...alll between 2000 and 350 seconds...and got mixed results).
Procedure:
-started at i.e. 800 seconds before ISS overflies my position, using standard ascent-AP to have a roughly correct launch heading of 42 degrees.
-accelerated to about 1800 m/s
-at about 30 kms altitude I disabled the (standard ascent)AP and trimmed up to max
-then I swithed over to direct-ascent AP, wile using the SCRAM engines to maintain the 1800 -2300 m/s, while bouncing between 30kms and 60 - 80 kms altitude.
-during this (manually)attitude corrections, have the feeleing, that I am allways "fighting" againts the direct-ascent AP, so sometimes it helps to switch off the PITCH-AP for a while
-when delta-T reaches about 20 seconds, I disable the SCRAM-engines and after a while the main-enigines are kicking-in controlled by direct-ascent-AP.
-at this point I have reached the point where it sometimes fails and sometimes succeeds
-if all goes well, the ship will be at about 5-10 kms form the ISS at a DV of about +/- 30 m/s
but sometimes:
-the AP banks left and right all the time and screws-up my delta-T, which causes the an a large offset to ISS....sometimes 600 kms+ (ISS has already passed my position, and I lost too much time during the left/right corrections)
I watched the included replay, which caused some confusions.
Here it was mentoined, that you have to enable the COR-AP, but it's allready "on" per default.
The videos on youtube are also not very helpfull, because they are not telling what MFD-button to push at which stage of the flight.
Is there any reliable procedure to use tis direct-ascent-AP, let's say with an XR-vessel?
In my case all successfull acents where more or less "luck".
I mean, I got some successfull results, but the target offsets were allways wrong...sometimes 10 kms sometimes...more than 800 kms.
I got also plenty of complete screwed-up launches.
In all tests, I am using the same starting scenario:
In the XR2 folder : "1 - Ready for takeoff to ISS".
I know, when the scenario loads-up, it's allready to late to start the direct-ascent, so I waited then to the next (ascending/42 degrees launch heading) node.
I started at at about 1000 seconds before the ISS would overfly my lauch position.
(I tested also different timings...alll between 2000 and 350 seconds...and got mixed results).
Procedure:
-started at i.e. 800 seconds before ISS overflies my position, using standard ascent-AP to have a roughly correct launch heading of 42 degrees.
-accelerated to about 1800 m/s
-at about 30 kms altitude I disabled the (standard ascent)AP and trimmed up to max
-then I swithed over to direct-ascent AP, wile using the SCRAM engines to maintain the 1800 -2300 m/s, while bouncing between 30kms and 60 - 80 kms altitude.
-during this (manually)attitude corrections, have the feeleing, that I am allways "fighting" againts the direct-ascent AP, so sometimes it helps to switch off the PITCH-AP for a while
-when delta-T reaches about 20 seconds, I disable the SCRAM-engines and after a while the main-enigines are kicking-in controlled by direct-ascent-AP.
-at this point I have reached the point where it sometimes fails and sometimes succeeds
-if all goes well, the ship will be at about 5-10 kms form the ISS at a DV of about +/- 30 m/s
but sometimes:
-the AP banks left and right all the time and screws-up my delta-T, which causes the an a large offset to ISS....sometimes 600 kms+ (ISS has already passed my position, and I lost too much time during the left/right corrections)
I watched the included replay, which caused some confusions.
Here it was mentoined, that you have to enable the COR-AP, but it's allready "on" per default.
The videos on youtube are also not very helpfull, because they are not telling what MFD-button to push at which stage of the flight.
Is there any reliable procedure to use tis direct-ascent-AP, let's say with an XR-vessel?
In my case all successfull acents where more or less "luck".
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Is there somewhere a detailed procedure, how to use the direct ascent AP, so it might work more reliable ?
No, I'm waiting for someone to produce a detailed YT clip about it, or RL allowing me to do it by myself. However there are few things that you always have to keep in mind..
First of all, don't try XR until you're proficient with DG-S
I mean, I got some successfull results, but the target offsets were allways wrong...sometimes 10 kms sometimes...more than 800 kms.
This might mean that you overshoot the orbit, indicated by the LAN Correction switched off along the way. Was it still on just before you entered orbit, or did it get disabled before? My bet is that it did, because of some mistakes you did. Let's get into details.
-started at i.e. 800 seconds before ISS overflies my position,
Good, but:
using standard ascent-AP to have a roughly correct launch heading of 42 degrees.
Use the DA-AP immediately after achieving maneuverable altitude. What it does might surprise you, but its objective is to bring the DG under the orbit ASAP, and keeping it there.
-then I swithed over to direct-ascent AP, wile using the SCRAM engines to maintain the 1800 -2300 m/s, while bouncing between 30kms and 60 - 80 kms altitude.
Firstly, you shouldn't let her to bounce, because it means that the AP looses maneuverability and can't do what's advertised.
Secondly, the speed is too large. Try to reduce it to 1500 m/s and stay lower. (this works for DG-S at least). If you travel too fast, then ISS will not reach you in a reasonable time, and the correction will stop working (see above), because you will cross the orbit, even when flying low. In general - get under orbit as fast as possible, and reduce speed, once you see that the equilibrium is reached, indicated by Time To Node being similar, but greater than Delta T, and Rinc under 5*.
Also, at these velocities you might have crossed the "Amplitude" of the orbit's ground track, and this is when the correction has no more chance to work. It this is the case, choose the southern (descending) solution from Cape, instead of the northern one. This will give you more time.
-during this (manually)attitude corrections, have the feeleing, that I am allways "fighting" againts the direct-ascent AP, so sometimes it helps to switch off the PITCH-AP for a while
There's no PITCH-AP component in DA. The trim control is left entirely to the pilot. And again, let the AP work, by flying lower.
-when delta-T reaches about 20 seconds, I disable the SCRAM-engines and after a while the main-enigines are kicking-in controlled by direct-ascent-AP.
Disable them just after reaching equilibrium mentioned earlier. If ISS is still far away, maintain minimal speed on SCRAMS and reenable them later, once ISS gets closer.
but sometimes:
-the AP banks left and right all the time and screws-up my delta-T, which causes the an a large offset to ISS....sometimes 600 kms+ (ISS has already passed my position, and I lost too much time during the left/right corrections)
I'd like to see if/when this happens, if you fly low enough.
I watched the included replay, which caused some confusions.
Here it was mentoined, that you have to enable the COR-AP, but it's allready "on" per default.
Yeah, it's on, so you don't have to worry about it per default. But if it's off, then you now know that you have to enable it. Where's the problem?
The videos on youtube are also not very helpfull, because they are not telling what MFD-button to push at which stage of the flight.
But there's no button pushing other than enabling the AP, which I believe is pretty obvious anyway.
Well, good luck.
No, I'm waiting for someone to produce a detailed YT clip about it, or RL allowing me to do it by myself. However there are few things that you always have to keep in mind..
First of all, don't try XR until you're proficient with DG-S
I mean, I got some successfull results, but the target offsets were allways wrong...sometimes 10 kms sometimes...more than 800 kms.
This might mean that you overshoot the orbit, indicated by the LAN Correction switched off along the way. Was it still on just before you entered orbit, or did it get disabled before? My bet is that it did, because of some mistakes you did. Let's get into details.
-started at i.e. 800 seconds before ISS overflies my position,
Good, but:
using standard ascent-AP to have a roughly correct launch heading of 42 degrees.
Use the DA-AP immediately after achieving maneuverable altitude. What it does might surprise you, but its objective is to bring the DG under the orbit ASAP, and keeping it there.
-then I swithed over to direct-ascent AP, wile using the SCRAM engines to maintain the 1800 -2300 m/s, while bouncing between 30kms and 60 - 80 kms altitude.
Firstly, you shouldn't let her to bounce, because it means that the AP looses maneuverability and can't do what's advertised.
Secondly, the speed is too large. Try to reduce it to 1500 m/s and stay lower. (this works for DG-S at least). If you travel too fast, then ISS will not reach you in a reasonable time, and the correction will stop working (see above), because you will cross the orbit, even when flying low. In general - get under orbit as fast as possible, and reduce speed, once you see that the equilibrium is reached, indicated by Time To Node being similar, but greater than Delta T, and Rinc under 5*.
Also, at these velocities you might have crossed the "Amplitude" of the orbit's ground track, and this is when the correction has no more chance to work. It this is the case, choose the southern (descending) solution from Cape, instead of the northern one. This will give you more time.
-during this (manually)attitude corrections, have the feeleing, that I am allways "fighting" againts the direct-ascent AP, so sometimes it helps to switch off the PITCH-AP for a while
There's no PITCH-AP component in DA. The trim control is left entirely to the pilot. And again, let the AP work, by flying lower.
-when delta-T reaches about 20 seconds, I disable the SCRAM-engines and after a while the main-enigines are kicking-in controlled by direct-ascent-AP.
Disable them just after reaching equilibrium mentioned earlier. If ISS is still far away, maintain minimal speed on SCRAMS and reenable them later, once ISS gets closer.
but sometimes:
-the AP banks left and right all the time and screws-up my delta-T, which causes the an a large offset to ISS....sometimes 600 kms+ (ISS has already passed my position, and I lost too much time during the left/right corrections)
I'd like to see if/when this happens, if you fly low enough.
I watched the included replay, which caused some confusions.
Here it was mentoined, that you have to enable the COR-AP, but it's allready "on" per default.
Yeah, it's on, so you don't have to worry about it per default. But if it's off, then you now know that you have to enable it. Where's the problem?
The videos on youtube are also not very helpfull, because they are not telling what MFD-button to push at which stage of the flight.
But there's no button pushing other than enabling the AP, which I believe is pretty obvious anyway.
Well, good luck.
Many thanks for all the hints, that was exactly what I was searching for. :thumbup:
So I have much stuff to test.
In my case:
-I need to fly slower and lower, because the main-problem could be:
Esp. the "reasonable time" was maybe a bit to long in my tests, so the AP was confused.
-I should enable direct-acent-AP a couple of seconds after leaving the runway...not using the standard-AP.
Btw., I have done this to avoid the 180-degrees(pointing to ISS) turn right after take-off...however, I will try....
It would be a bit more helpfull to show the video just from the cockpit, no external-view switching. So one could see exactly whats going on within the MFD.
However, many thanks for the explanation, with all this input, I will find a permanent solution sooner or later. So my dream might come true, a regular all 12 hour pizza-delivery-service to the ISS.
---------- Post added at 10:49 PM ---------- Previous post was at 08:48 PM ----------
Ok, I have tried it again, this time I started southbound and used the DA-AP right after reaching a stable flight.
All went fine, I climbed to about 30 kms and estabished a stable speed at 1300 m/s.
The AP then directed the vessel into the direction of the node, which was fine and stable.
When reached t-delta 0, the DA-AP fired-up main-engine thrust and pitched up...as expected.
But during the (stable...no left/right-banking) ascent, the t-delta and t-meco drifted more and more.
So a the end, I was abaut 65 seconds too late in a stable orbit.. 500 kms behind the ISS.
During the entire flight, the LAN-corection was active (no red -) and performed well.
So maybe 1300 m/s is too slow ?
Will do more testing....
So I have much stuff to test.
In my case:
-I need to fly slower and lower, because the main-problem could be:
Esp. the "reasonable time" was maybe a bit to long in my tests, so the AP was confused.
-I should enable direct-acent-AP a couple of seconds after leaving the runway...not using the standard-AP.
Btw., I have done this to avoid the 180-degrees(pointing to ISS) turn right after take-off...however, I will try....
Ok, if it's just hitting direct ascent "AP"....you are right. But I was not sure about this, esp. because the 180 degrees-issue as mentioned above.
It would be a bit more helpfull to show the video just from the cockpit, no external-view switching. So one could see exactly whats going on within the MFD.
However, many thanks for the explanation, with all this input, I will find a permanent solution sooner or later. So my dream might come true, a regular all 12 hour pizza-delivery-service to the ISS.
---------- Post added at 10:49 PM ---------- Previous post was at 08:48 PM ----------
Ok, I have tried it again, this time I started southbound and used the DA-AP right after reaching a stable flight.
All went fine, I climbed to about 30 kms and estabished a stable speed at 1300 m/s.
The AP then directed the vessel into the direction of the node, which was fine and stable.
When reached t-delta 0, the DA-AP fired-up main-engine thrust and pitched up...as expected.
But during the (stable...no left/right-banking) ascent, the t-delta and t-meco drifted more and more.
So a the end, I was abaut 65 seconds too late in a stable orbit.. 500 kms behind the ISS.
During the entire flight, the LAN-corection was active (no red -) and performed well.
So maybe 1300 m/s is too slow ?
Will do more testing....
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Yes, it could have been too slow (just before injection), but was it still XR? Was its main engine running with full power? In that case, there was no room for the automatic control to lower the DT to 0, because it manipulates the engine power up and down, to achieve this. The cause could also be too high relative inclination before injection. Then a lot of the engine power is used up for the plane change.
It would be a bit more helpfull to show the video just from the cockpit, no external-view switching. So one could see exactly whats going on within the MFD.
This is what the playback scenarios are for. The external view clip is just a showoff.
It would be a bit more helpfull to show the video just from the cockpit, no external-view switching. So one could see exactly whats going on within the MFD.
This is what the playback scenarios are for. The external view clip is just a showoff.
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Initialy the engines were running at about 80 percent...maybe a bit less.
But...yes...at the point where the DA-AP started its ascent to ISS, the rel. INC was >20 degrees, which went down to 0 at the end.
I started with an inital lower RINC, but the AP increased the RelINC to max 25 degrees during the sub-orbital-flight.
I tested again...and I don't get the logic behind the AP:
-same issue 600+ kms behind the ISS
What is the point to accelerate "against" the node (180 degrees flip) during the early stages of the AP ?
(i.e southbound-launch results in a 42 degrees profile, which is exactly 180 degrees into the wrong direction)
Then later on, the AP tries to correct the (self-increased RINC) again(so we are wasting fuel and time), and the vessel runs out-off power to catch up with the ISS too late in orbit with 0 RINC.
Very late in the flight, I can see the the AP is going to 100 percent...(but to catch up the ISS the AP might need i.e. 150 pecent).
Maybe the best would be to fly complete manually and try to use the AP when delta-T reaches 0 ?
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Enjo
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The AP isn't an intelligent algorithm, so maybe you're right, but.... are you sure that you're launching before the orbit's plane crosses your launch site? If it does, then choosing the other direction is a natural thing.
>are you sure that you're launching before the orbit's plane crosses your launch site?
Yes...of course, plenty of time left to node, it's allways positive and "CORR" never disables during the netire flight.
>The AP isn't an intelligent algorithm, so maybe you're right...
The AP is much clever, and I am sure, that I am doing something wrong.
The problem with the AP is the very early stage.
I have seen within this thread, that some people have issues, too, esp in later version of LaunchMFD.
If my understanding is correct, you have changed the "early-follow-the-node-logic", to avoid to reach "0" rel.INC too soon in a flight(where delta-t is still high).
In earlier versions, I have had more success with direct-ascent.
I.e. if launched a very high powered-ship, where I have lauched much much later.
So I skipped the entire sub-orbital part, and went direct into the right plane and was still able to reach the ISS just in time.
However I did some more tests, and still cannot get to a stable solution.
9 out of 10 launches are failures.
Only one launch was successfull, where I have forced the direction/heading to keep rel.INC low...but not too low.
So it as more or less luck. I bounced up-and down, banked and left and right like crazy...and somehow I was 150 meters before the ISS at the end.
To keep it simple, I still use the XR2, but not usng SCRAM.
I have set a high ISP, so I can rely on main-engines (for testing only).
After launch, I try to reach 30 kms altitude as fast as possible and keep a velocity at about 1000 - 1300 m/s.
At this speed I can use the trim to have a relative stable altitude betwen 30 and 40 kms.
So its more or less the same profile, like the DG-S at this stage.
Again, if I let do the AP the entire job, rel-INC goes up to like 78 degrees...and this seems to be a bit too much. (even that I have rel.INC "0" at the end...but the ISS has already passed my position and is hundreds of kms away form my final position.
(caused by the very late (maybe too late) rel-INC correction.
Yes...of course, plenty of time left to node, it's allways positive and "CORR" never disables during the netire flight.
>The AP isn't an intelligent algorithm, so maybe you're right...
The AP is much clever, and I am sure, that I am doing something wrong.
The problem with the AP is the very early stage.
I have seen within this thread, that some people have issues, too, esp in later version of LaunchMFD.
If my understanding is correct, you have changed the "early-follow-the-node-logic", to avoid to reach "0" rel.INC too soon in a flight(where delta-t is still high).
In earlier versions, I have had more success with direct-ascent.
I.e. if launched a very high powered-ship, where I have lauched much much later.
So I skipped the entire sub-orbital part, and went direct into the right plane and was still able to reach the ISS just in time.
However I did some more tests, and still cannot get to a stable solution.
9 out of 10 launches are failures.
Only one launch was successfull, where I have forced the direction/heading to keep rel.INC low...but not too low.
So it as more or less luck. I bounced up-and down, banked and left and right like crazy...and somehow I was 150 meters before the ISS at the end.
To keep it simple, I still use the XR2, but not usng SCRAM.
I have set a high ISP, so I can rely on main-engines (for testing only).
After launch, I try to reach 30 kms altitude as fast as possible and keep a velocity at about 1000 - 1300 m/s.
At this speed I can use the trim to have a relative stable altitude betwen 30 and 40 kms.
So its more or less the same profile, like the DG-S at this stage.
Again, if I let do the AP the entire job, rel-INC goes up to like 78 degrees...and this seems to be a bit too much. (even that I have rel.INC "0" at the end...but the ISS has already passed my position and is hundreds of kms away form my final position.
(caused by the very late (maybe too late) rel-INC correction.
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Enjo
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I see your point.
Could I ask you to prepare a playback of the situation, now that we have the way clear of obvious mistakes?
Could I ask you to prepare a playback of the situation, now that we have the way clear of obvious mistakes?
Hmm...I should do direct-ascents only with "replay-mode" enabled.
I tried to record a typical failed launch...and ended up with a more or less successfull launch.
But even here, we can see that d-time starts to differ at a very late stage.
I set the offset-distance to "-250" and ended up at about 1.8 kms from ISS.
That's fine for me, but got better results in the past (with earlier LaunchMFD versions).
However, I need to watch the replay on my own, too.
Just to have an understanding what the hell I have done.:blink:
The problem was, as you can see, the launch.
I pitched-up for too long, and had a hard time to perform a stable altitude.
But at the end...all was more or less stable. (except the small time-drift at the end)
So just ignore my non-existent sub-orbital flying skills during the first minutes of this flight.:facepalm:
I will try something like this later, but this time...soutbound.
So it seems to be 600-500 seconds d-satelite might be enough.....
In previous tests, I launched earlier...about 800 seconds.
Btw, I enabled the AP after launch when the vessel crossed the 3600 meters-mark(you can hear then the RCS'es are fighting for the heading, while I pitched-up and down like crazy...
I tried to record a typical failed launch...and ended up with a more or less successfull launch.
But even here, we can see that d-time starts to differ at a very late stage.
I set the offset-distance to "-250" and ended up at about 1.8 kms from ISS.
That's fine for me, but got better results in the past (with earlier LaunchMFD versions).
However, I need to watch the replay on my own, too.
Just to have an understanding what the hell I have done.:blink:
The problem was, as you can see, the launch.
I pitched-up for too long, and had a hard time to perform a stable altitude.
But at the end...all was more or less stable. (except the small time-drift at the end)
So just ignore my non-existent sub-orbital flying skills during the first minutes of this flight.:facepalm:
I will try something like this later, but this time...soutbound.
So it seems to be 600-500 seconds d-satelite might be enough.....
In previous tests, I launched earlier...about 800 seconds.
Btw, I enabled the AP after launch when the vessel crossed the 3600 meters-mark(you can hear then the RCS'es are fighting for the heading, while I pitched-up and down like crazy...
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This is Flights subfolder. I also need a scenario file from the Scenarios/Playback folder.
Also, I'd urge you to try the DG-S first.
Also, I'd urge you to try the DG-S first.
Sorry, I don't have much experience wth playback-mode.
Missing scn-file is attached.
Btw. I tried the XR1 this time soutbound.
Same profile, but much more stable initial flight-phase. (but no replay...)
Here I used the mre realistic weaker engine-option, which matches more the default-DG.
All went fine, right before final-ascent RINC was 5.6 degrees, but later on, the time starts to drift again.
It ended up with delta-t -35 seconds, so I was about 150 kms behind the ISS.
Maybe the AP might get confused with the XR-vessel-atmosphere-reduction-thrust-option (thrust was at 80 percent at the beginning od the final.ascent, then increased to max after a while)?
Missing scn-file is attached.
Btw. I tried the XR1 this time soutbound.
Same profile, but much more stable initial flight-phase. (but no replay...)
Here I used the mre realistic weaker engine-option, which matches more the default-DG.
All went fine, right before final-ascent RINC was 5.6 degrees, but later on, the time starts to drift again.
It ended up with delta-t -35 seconds, so I was about 150 kms behind the ISS.
Maybe the AP might get confused with the XR-vessel-atmosphere-reduction-thrust-option (thrust was at 80 percent at the beginning od the final.ascent, then increased to max after a while)?
Finaly I did a test with the default DG.
I used the same proifle/start-up conditions.
Sub-orb-flight at 1300-1500 m/s at an altitude of about 32 kms.
Here all went fine, no wild left/right banking etc...I set "-250" meters offset and ended up with 310 meters below the ISS.
So perfect...as long as using the stock DG.
What might causing the XR vessel to behave so different ?
Ok., the stock DG seems to be reacting more agile to attitude/bank changes.
Maybe a bit too "agile" for a vessel wich has a weight of 20+ tons.
Do you have any idea, what we can do to make the XRs performing better with the direct-ascent AP ?
Using cheatcodes for stronger RCS ?
But I believe it's more an aerodynamic issue....:hmm:
I used the same proifle/start-up conditions.
Sub-orb-flight at 1300-1500 m/s at an altitude of about 32 kms.
Here all went fine, no wild left/right banking etc...I set "-250" meters offset and ended up with 310 meters below the ISS.
So perfect...as long as using the stock DG.
What might causing the XR vessel to behave so different ?
Ok., the stock DG seems to be reacting more agile to attitude/bank changes.
Maybe a bit too "agile" for a vessel wich has a weight of 20+ tons.
Do you have any idea, what we can do to make the XRs performing better with the direct-ascent AP ?
Using cheatcodes for stronger RCS ?
But I believe it's more an aerodynamic issue....:hmm:
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Ah finally
You're a tester, right? Sorry to get on your ambitions, but to solve complex problems, it's wise to isolate the problem as much as possible, by reducing influences on it.It's definitely an aerodynamic issue. It's known that DG has an artificially high lift (here, used for turning), but it's a stock vessel, and I have to support it before others.
Other than that, supporting XR would also be good. I remember that it was working fine, but probably before I changed that plane correction algo. Maybe I forgot to test it on XR afterwards. At least now I have a pointer, that no other member ever noticed :tiphat:
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Yes....I was tester,trouble-shooter/maker....fly+fix guy, ...and whatever they called me.
The problem I have had with standard DG is the (IMO) poor reentry capabilities.
I like to fly to ISS and do a rentry afterwards...just to bring the mission to an end.
But thanks to GS2 and Aerobrake MFD's autopilot, I am now able to perform some "-1.8 degrees AOA...forget about dynamic-pressure reentries"). :facepalm:
So....I tested a bit more, even in Orbiter2016, which works exactly the same btw.
Using the standard DG a got 9 out of 10 direct-acents successfull (-/+ 5 10 kms offset).
But sometimes the AP directs to long "against" the plane, so when it comes to final ascent, there might be 25 degrees RINC...which is to much, and the vessel runs out of power/delta-time.
I believe 7-5 degrees RINC before final ascent seems to be perfect.
Yes, I agree, the velocity pointer acts much more faster to direction/pitch changes compared to the XR vessels.
Maybe we need a different AP-profile for XR vessels, where the AP does not expect the velocity-vector changes so quickly like in the DG. (?)
Enjo
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Definitely, and more testing time. What we have now is a classic case of over-fitting to a certain type of vessel.
I think I'll get back to development soon, but not tomorrow.
No hurry...just good to know, that you will take care.
And also good to know, that I am not doing everything complete wrong (except used the "wrong" vessel).
Just done some more testing, not just ISS.
It might be random, but it seems to be that higher satelites are causing the direct-ascent to be super-precise. I.e. I put a space-station into a 30 degrees inc. at about 500 kms altitude.
At MECO, I had a (exact-below)distance of 253 meters (was set to "-250").
The rel.vel was below 3 m/s...so...:tiphat:
Btw..just to summarize, how I am now doing those direct-ascents, in case somebody else has similar issue:
ISS direct-ascent:
-using stock DG...maybe DG-S might be the better choice
-starting LaunchMFD and set target to ISS, then go straight into DA-mode
-just in case...set a below-offset to ISS, using "alt" button(i.e. "-250")
-waiting for a good launch windows (i.e. delta-satelite 600+ seconds and time to node about 3000-5000 seconds...worked fine for me)
-launch just straight to reach a stable flght profile (i.e. 250+ m/s)
-just hit AP to let the AP whatever "he" likes (even that it might look confusing(RINC increasing etc.) at the very early flight
-try to reach about 30 kms atlitude as fast as possible, but be careful not to overshoot too much
-at 30 kms alt, trim-up and let the vessel accelerate to about 1300-1700 m/s
-make sure that there are no more harsh velocity changes or alt-changes happening (full trim is doing great job..to hold the vessel quite stable after some small bumps).
-wait...you could even use tme-skip 10x, if stable altitude/attitude until delta-t is about 20 seconds
-enjoy the the dramatical high-speed-approach to ISS
And also good to know, that I am not doing everything complete wrong (except used the "wrong" vessel).
Just done some more testing, not just ISS.
It might be random, but it seems to be that higher satelites are causing the direct-ascent to be super-precise. I.e. I put a space-station into a 30 degrees inc. at about 500 kms altitude.
At MECO, I had a (exact-below)distance of 253 meters (was set to "-250").
The rel.vel was below 3 m/s...so...:tiphat:
Btw..just to summarize, how I am now doing those direct-ascents, in case somebody else has similar issue:
ISS direct-ascent:
-using stock DG...maybe DG-S might be the better choice
-starting LaunchMFD and set target to ISS, then go straight into DA-mode
-just in case...set a below-offset to ISS, using "alt" button(i.e. "-250")
-waiting for a good launch windows (i.e. delta-satelite 600+ seconds and time to node about 3000-5000 seconds...worked fine for me)
-launch just straight to reach a stable flght profile (i.e. 250+ m/s)
-just hit AP to let the AP whatever "he" likes (even that it might look confusing(RINC increasing etc.) at the very early flight
-try to reach about 30 kms atlitude as fast as possible, but be careful not to overshoot too much
-at 30 kms alt, trim-up and let the vessel accelerate to about 1300-1700 m/s
-make sure that there are no more harsh velocity changes or alt-changes happening (full trim is doing great job..to hold the vessel quite stable after some small bumps).
-wait...you could even use tme-skip 10x, if stable altitude/attitude until delta-t is about 20 seconds
-enjoy the the dramatical high-speed-approach to ISS
Last edited:
Enjo
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It's pretty normal - at higher altitudes the speed is much slower and the automatic control finds it easier to follow the required value (DeltaT = 0).
What I find intriguing, is that at higher launch site latitudes, the AP performs worse, and I fail to find an explaination.
Yes it would be, for the reason that you can setup the SCRAMS to a certain level fire-and-forget way - your speed won't exceed 2000 m/s and stability is easier to reach.
The latest version of LaunchMFD_2016 has some strange default values.
The default altitude right after launching LaunchMFD shows me 2520 km instead of 220 km like before.
Not a real problem...I just want to report this to avoid one to become a "highflyer" per accident.
The default altitude right after launching LaunchMFD shows me 2520 km instead of 220 km like before.
Not a real problem...I just want to report this to avoid one to become a "highflyer" per accident.
Nicholas Kang
Tutorial Publisher
The latest version of LaunchMFD_2016 has some strange default values.
The default altitude right after launching LaunchMFD shows me 2520 km instead of 220 km like before.
Not a real problem...I just want to report this to avoid one to become a "highflyer" per accident.
I can confirm this anomaly as well. I suppose Enjo will not take us that high.:lol:
220 km is just nice enough to appreciate the beauty of magnificent Earth and for basic flight test.
Nicholas.
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