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There's a lack of reentry tutorials, especially for beginners, i want to share my experience how to bring the DG-IV back home.
You should:
* - read ar81's Concepts for atmospheric reentry tutorial first, it can be found [ame="http://www.orbithangar.com/searchid.php?ID=3428"]here[/ame]. It will help you understand what it takes to bring you bird back down.
* - be familiar with the DG-IV (how to use the flight computer and the basic controls)
You will need:
[ame="http://www.orbithangar.com/searchid.php?ID=2139"]AerobreakMFD[/ame]
BasesyncMFD
[ame="http://www.orbithangar.com/searchid.php?ID=3666"]Wideawake International[/ame]
DeltaGliderIV
Update: made a video, hosted on vimeo.com, unfortunately the aspect ratio is now off which makes the MFDs hard to read. i will look in to it. if you are registered on vimeo you can download the original video which is 140mb big but has the right aspect ratio.
[ame="http://www.vimeo.com/4987103"]DeltaGliderIV reentry video[/ame]
Let's Start:
Load the Scenario "DeltaGliderIV/Earth Scenary/Docked to Mir"
- undock from Mir, close your Nose Cone, turn HYD Pressure off.
- open Map MFD select Wideawake International as target.
- open COM/NAV MFD set Nav1 to 113.30 (Runway 12 at Wideawake, the long one in the center) set Nav2 to 113.00 (Wideawake Navbeacon)
- open BasesyncMFD on the right. click on TGT, type in Wideawake International hit enter. click on E/D this will switch BasesyncMFD between equatorial and direct mode, we need direct.
- open AerobrakeMFD on the left, click on TGT, type Wideawake International hit enter. click on PG (this will set AerobrakeMFD to the Graph/Map mode) click on PRJ so we see the Map display
your MFDs should look like this:
- start Orbit (-) Normal autopilot when you reach the ascending node and burn until our 4th orbit pases within 2km over Wideawake International
Basesync Should look like this:
- speed up time until you reach the opposite side of the planet on our last orbit, start the retrograde autopilot. hit D2 on your keyboard to activate the DG-IV's "Deorbiting Display". you will see on the AerobreakMFD your flight path directly over Wideawake International.
Start your burn:
- burn till Pea reads 60km and Reentry Angle Prediction about 0.7° on the D2 display
- AerobreakMFD shows that we are a tiny bit off, but thats ok for now. type D65 (reentry check). close your hover and retro doors, select surface MFD on the right, change HUD to surface. pump rcs fuel to the main tank, leave about 110kg in the rcs tank (if we have to start our main engines to reach our base, it is better to have the fuel in the main tank, the reentry autopilot will use 5-10 kg rcs fuel, if we leave ~110kg we won't be nagged by the low fuel alarm).
- speed time up until you alt reads 160km. engage the manual reentry autopilot to an AOA of 40° (p104s40 on the keyboard)
you will see that my flight path is not directly over Wideawake International
- adjust your bank so that our flight path is directly over Wideawake International (only works in 5° steps with the p104s40 autopilot but thats enough, 10° did it for me)
- you can speed time up till the autopilot disengages the timewarp automatically at about 90km altitude, switch your DG-IV flight computer display to "Reentry Control Display" (D3 on your keyboard)
- you see that i will over shoot Wideawake, i pull up to 60° AOA for a few seconds so that i adjust my reentry over the base (depends on your altitude how long it will take, its better to do this while you are still over 70km alt, if you are to short pull down to 30° AOA)
take a drink and watch your descent
- if you you try for a unpowered landing, you will need too keep an eye on the target distance (this can be found on our AerobreakMFD, the value is " " Dist:") and hold it at 2km. to do this you will have to adjust your AOA constantly. it is important that you hold more or less that 40° AOA only for a very short period of time. you will use more rcs fuel doing this, transfer 10kg back in the rcs tank to be on the save side. we don't want to be distracted from the low fuel alarm.
- at 47km altitude our hull temperature reads 1605° C it won't go much higher if you did it right.
- at 25km alt switch the ship control to "elevon & gear", and switch the HYD gear pressure on. select HSI MFD on the left, (we don't need AerobreakMFD anymore) disengage the reentry autopilot! watch your G-force and your hull temperature while you turn and align with the Runway. fire up your main engines if you are to far from the base. it is better to be a bit too fast than to come in to short. if you try to land without firring you main engines again try to hold 8 km altitude when you reach a distance of 5km from the runway, pitch down aim for the runway safety area. start pulling up at 2km alt. don't get too fast use your speedbrake if you are going over 300m/s (the D3 display shows the status of the speedbrake) when you reach 500m drop very slowly you altitude.
open your gear and try bringing the glider down as gently as possible. don't forget the Runway is almost 5km long and the DG-IV has good brakes, you have time to land.
had some trouble aligning with the runway and going too fast
this led to the destruction of the landing gear
last words:
- don't exceed 19t kg ship weight (the reentry autopilots wont start if you are too heavy)
- remember to switch the HYD Pressure back on before you attempt to land
- a complete unpowered landing is unforgiving (is way easier with the XR-1, the aerodynamics of the DG-IV are not the best for beginners)
- don't forget to switch the ship control to "elevon & gear". at least 3 times the "atm auto" switched to rcs on the last few meters and killed my crew or disabled my ship.
- save between the burns, and especially before your landing (it's quite annoying losing the ship on the last few hundred meters)
- if you can get the DG-IV back home it will be easy with the XR - family
hope this helps you bring the DG-IV back home.
reentry and a complete unpowered landing, is the most challenging and most fun thing i came across in orbiter, don't feel bad if you don't succeed at your first attempt.
You should:
* - read ar81's Concepts for atmospheric reentry tutorial first, it can be found [ame="http://www.orbithangar.com/searchid.php?ID=3428"]here[/ame]. It will help you understand what it takes to bring you bird back down.
* - be familiar with the DG-IV (how to use the flight computer and the basic controls)
You will need:
[ame="http://www.orbithangar.com/searchid.php?ID=2139"]AerobreakMFD[/ame]
BasesyncMFD
[ame="http://www.orbithangar.com/searchid.php?ID=3666"]Wideawake International[/ame]
DeltaGliderIV
Update: made a video, hosted on vimeo.com, unfortunately the aspect ratio is now off which makes the MFDs hard to read. i will look in to it. if you are registered on vimeo you can download the original video which is 140mb big but has the right aspect ratio.
[ame="http://www.vimeo.com/4987103"]DeltaGliderIV reentry video[/ame]
Let's Start:
Load the Scenario "DeltaGliderIV/Earth Scenary/Docked to Mir"
- undock from Mir, close your Nose Cone, turn HYD Pressure off.
- open Map MFD select Wideawake International as target.
- open COM/NAV MFD set Nav1 to 113.30 (Runway 12 at Wideawake, the long one in the center) set Nav2 to 113.00 (Wideawake Navbeacon)
- open BasesyncMFD on the right. click on TGT, type in Wideawake International hit enter. click on E/D this will switch BasesyncMFD between equatorial and direct mode, we need direct.
- open AerobrakeMFD on the left, click on TGT, type Wideawake International hit enter. click on PG (this will set AerobrakeMFD to the Graph/Map mode) click on PRJ so we see the Map display
your MFDs should look like this:
- start Orbit (-) Normal autopilot when you reach the ascending node and burn until our 4th orbit pases within 2km over Wideawake International
Basesync Should look like this:
- speed up time until you reach the opposite side of the planet on our last orbit, start the retrograde autopilot. hit D2 on your keyboard to activate the DG-IV's "Deorbiting Display". you will see on the AerobreakMFD your flight path directly over Wideawake International.
Start your burn:
- burn till Pea reads 60km and Reentry Angle Prediction about 0.7° on the D2 display
- AerobreakMFD shows that we are a tiny bit off, but thats ok for now. type D65 (reentry check). close your hover and retro doors, select surface MFD on the right, change HUD to surface. pump rcs fuel to the main tank, leave about 110kg in the rcs tank (if we have to start our main engines to reach our base, it is better to have the fuel in the main tank, the reentry autopilot will use 5-10 kg rcs fuel, if we leave ~110kg we won't be nagged by the low fuel alarm).
- speed time up until you alt reads 160km. engage the manual reentry autopilot to an AOA of 40° (p104s40 on the keyboard)
you will see that my flight path is not directly over Wideawake International
- adjust your bank so that our flight path is directly over Wideawake International (only works in 5° steps with the p104s40 autopilot but thats enough, 10° did it for me)
- you can speed time up till the autopilot disengages the timewarp automatically at about 90km altitude, switch your DG-IV flight computer display to "Reentry Control Display" (D3 on your keyboard)
- you see that i will over shoot Wideawake, i pull up to 60° AOA for a few seconds so that i adjust my reentry over the base (depends on your altitude how long it will take, its better to do this while you are still over 70km alt, if you are to short pull down to 30° AOA)
take a drink and watch your descent
- if you you try for a unpowered landing, you will need too keep an eye on the target distance (this can be found on our AerobreakMFD, the value is " " Dist:") and hold it at 2km. to do this you will have to adjust your AOA constantly. it is important that you hold more or less that 40° AOA only for a very short period of time. you will use more rcs fuel doing this, transfer 10kg back in the rcs tank to be on the save side. we don't want to be distracted from the low fuel alarm.
- at 47km altitude our hull temperature reads 1605° C it won't go much higher if you did it right.
- at 25km alt switch the ship control to "elevon & gear", and switch the HYD gear pressure on. select HSI MFD on the left, (we don't need AerobreakMFD anymore) disengage the reentry autopilot! watch your G-force and your hull temperature while you turn and align with the Runway. fire up your main engines if you are to far from the base. it is better to be a bit too fast than to come in to short. if you try to land without firring you main engines again try to hold 8 km altitude when you reach a distance of 5km from the runway, pitch down aim for the runway safety area. start pulling up at 2km alt. don't get too fast use your speedbrake if you are going over 300m/s (the D3 display shows the status of the speedbrake) when you reach 500m drop very slowly you altitude.
open your gear and try bringing the glider down as gently as possible. don't forget the Runway is almost 5km long and the DG-IV has good brakes, you have time to land.
had some trouble aligning with the runway and going too fast
this led to the destruction of the landing gear
last words:
- don't exceed 19t kg ship weight (the reentry autopilots wont start if you are too heavy)
- remember to switch the HYD Pressure back on before you attempt to land
- a complete unpowered landing is unforgiving (is way easier with the XR-1, the aerodynamics of the DG-IV are not the best for beginners)
- don't forget to switch the ship control to "elevon & gear". at least 3 times the "atm auto" switched to rcs on the last few meters and killed my crew or disabled my ship.
- save between the burns, and especially before your landing (it's quite annoying losing the ship on the last few hundred meters)
- if you can get the DG-IV back home it will be easy with the XR - family
hope this helps you bring the DG-IV back home.
reentry and a complete unpowered landing, is the most challenging and most fun thing i came across in orbiter, don't feel bad if you don't succeed at your first attempt.
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