Landing on a Runway

g2g591

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I can make it through reentry just fine and end up at the Cape, however, I can never actually get lined up and land on a runway. Does anyone have any tips?
 

MJR

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Establish localizer, orient yourself with that, follow glidescope. You must tune to the runway and switch to HSI.
 

PhantomCruiser

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MJR's right. I can do it by eye, but I'm a "stick and rudder" pilot and have been doing it for years.
Use the HSI's and practice, practice, practice.
If you have a "normal" flight simulator you can try using a Cessna (or whatever) and just do racetrack patterns all day long. Lauch-nose up-climb-crosswind turn (continue climbing)-turn downwind-decrease throttle-turn cross-turn final-flare-touchdown-advance throttle-repeat until wife makes you come to dinner.
Some of the detail oriented Sims will have it to where you need to perform every checklist item or "something bad" might happen (like forgetting carb heat and your engine seizes due to ice buildup after climb out). Then practice some more.
I haven't flown an actual aircraft in years (more than one decade but not two), but after years away from a plane (or even a flight Sim) a buddy wanted me to see how hard it was to land a Laser at Meigs field on his Sim.
He is still cussing me out. First try right on the centerline (but like I said it take practice).
 
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Tommy

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I've found the HSI not very usefull for getting an initial approach fix, it simply doesn't have enough range. At the speeds you're travelling at even this late in a re-entry, you need to be getting a fix before the HSI is in range. Yo really need to start planning for this fairlly early in the re-entry, I often do my base alignment with runway headings in mind.

The above advice is good, just fly around the airport and practice final approach/landing until you can do fairly consistantly. Don't forget you can widen the Field Of View, if the runway is off to one side this can help you get it in sight sooner. Once you're roughly aligned, you can tighten the FOV for more accuracy.

For an example of the HAC (Heading Alignment Cylinder) manuever, which is used when your re-entry path is at a high angle to the runway (often the case at canaveral) try the Home Direct tutorial. You can uncheck "play at recorded speed" and fast forward to the end of the inverted phase of the re-entry.

[ame="http://www.orbithangar.com/searchid.php?ID=3660"]Home Direct[/ame]
 

mjessick

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> For an example of the HAC (Heading Alignment Cylinder) manuever, which is used when your re-entry path is at a high angle to the runway
The main reason to use it is that it allows the trajectory to be adjusted to match the energy available. (Sort of like keeping some slack in a loop of rope.) To keep more margin later in the mission you would use it whenever possible. if you have too much energy, you do it larger and higher. Low on energy, do it tighter. If you are very short of energy approaching the landing site, you can then go straight in instead.
 

insanity

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I've got years of sim experience and a few hours of real flight-time and can land visually with relative ease, but I usually go for the HSI. I make a heading correction towards the end of reentry so that I can fly a base to final deadstick. Once I've got the fix correct, it is all about following the glidescope and watching your speed. I'd much rather fly the ILS properly then end up with a snapped gear or a dead crew because I rushed my landing.
 
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cr1

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Nice tutorials ibjammin! Now trying landing again :)
 

garyw

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This is one reason I've been wanting a "GPS MFD", HSI doesn't have good enough range so flying to a fix to initiate the HAC would be good.

I guess it would be possible to use Axial MFD and a VOR....
 

V8Li

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Practice.

I head 30 deg plus runway heading, turn when I'm about 20 miles from runway. This depends on my speed and altitude. ILS might or might not help. I don't use it anymore since I have anything sorted with experience (like bank angle which dictates the turning rate, speed, altitude and vertical speed). I empty my tanks before reentry anyway so the ship is light.
 

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This is one reason I've been wanting a "GPS MFD", HSI doesn't have good enough range so flying to a fix to initiate the HAC would be good.

I guess it would be possible to use Axial MFD and a VOR....
Have you seen kwan's [ame="http://www.orbithangar.com/searchid.php?ID=2763"]Glideslope MFD[/ame] on Orbit Hangar? It is designed for the Space Shuttle but I've often thought about modifying it so that trajectory files could be loaded for other vehicles. I don't have the time or energy presently, but if anyone reading this thread wants to, the source code is included in the download and the license is LGPL.
 

cr1

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By the way, why does my DGIV not respond to my "nose up" commands anymore? I crashed because of that while I was already just a few meters from the runway! Is it anything to do with ATM AUTO?
 

agentgonzo

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By the way, why does my DGIV not respond to my "nose up" commands anymore? I crashed because of that while I was already just a few meters from the runway! Is it anything to do with ATM AUTO?
No idea. ATM AUTO is atmospheric auto, meaning that if it detects that it's in the atmosphere, it will use the aerodynamic control surfaces to change attitude, and the RCS if it's in space. ATM AUTO is the correct mode to be in.

I'm assuming that you have hydraulic pressure and all the systems on?
 

IthyStPete

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Well, if you're on ATM AUTO, it'll sometimes switch to RCS right as you're landing due to your low speed. I almost always switch to elevon & gear by the time I'm on final approach so I don't randomly crash.
 

cr1

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OK tried my first landing with XR-2. It is much easier to control for flying and glides a lot better than DGIV, it seems. Except that maybe I relied on gliding for too long... so that I nearly stalled at "touchdown" and the VS was -8m/s. The gear collapsed. :(
Time to read the manual! Oh and also maybe I flared up too late.

EDIT: What are the stall speeds on Earth for the XRs?
 

Urwumpe

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EDIT: What are the stall speeds on Earth for the XRs?

The XRs are delta wing planes, they don't have a stall speed as such. You just loose lift until you drop like a stone.

Also, stall speed is the wrong number to look for during landing. You don't want to stall, you want to fly on the runway with enough control over it.

From the basic flight school of Urwumpe, for getting used with any winged vessel:

Landing starts with the approach. As we do spaceplanes, approach means energy management and alignment. We want to reduce the speed so we are not too fast, and align with the runway at the right distance. The best way to do so is the HAC approach.

This requires some training to get the targeting right, but is generally more successful as copying jetliner landing strategies. Usually, you will do a overhead approach: You pass over one end of the runway in 11000m altitude, and count to 10 (roughly). Then you do a steep turn towards the runway, loosing altitude quickly. While you gain maybe a bit of speed that way, you will loose most energy to drag. At the end of the turn, you should be roughly aligned with the runway.

If you are too far away from alignment, change the time from passing over the runway to initiation of the HAC turn. My experience is, that you can eyeball it pretty easy, and also can integrate nav beacons into it.

Practise to end the HAC in about 2500 m altitude and about 6000m distance to the runway (25° glideslope). This is the most critical part, but can be learned easily.Using the HSI and ILS is recommended, as both help you to manage the turn and get out of it right on the glidepath to the runway (the vertical plane passing through the runway).

Drop towards the beginning of the runway lights. In 500m altitude, start to pull slowly up (preflare) and point the velocity vector indicator at the point where you want to land. You should now also intercept the 3° ILS glide slope. You will loose speed quickly now, so be prepared to pull gently up over time to stay on the 3° glide slope.

In 150m altitude, lower gear, if you didn't do so. You will now loose much more speed. Pass over the runway threshold and pull up (flare). you will now quickly loose vertical velocity and even more quickly loose speed to the increased drag. If you do the flare at too high altitude, you will drop hard on the runway.

In this appraoch, speed is everything. Too slow and you will drop before reaching the runway, too fast and you will have problems getting on the runway with main gear first. My personal rule: You are too fast, if you can fly on the 3° glideslope without having the nose above the horizon.

The real numbers depend on the plane you fly. Instead of learning to fly by the numbers, learn to trust your eyes and feeling and use known numbers only as rough guide to the runway.

Any landing is successful, as long as you get down in one piece and did not overshoot the runway.
 

V8Li

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Try to land with less than 1m/s VS. It depends on the weight anyway, 2.5 for full load and 4 for an empty XR1 (if I remember well). Never used XR2.

If you are using a joystick you may land with less speed like 100m/s. If you're using the keyboard with the DG4 (which doesn't have great trim) land at 200m/s+ to have plenty of dynamic pressure so that the controls are effective and responsive.
 

cr1

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Yay, I'm not that bad at landing actually! Landed all three XR planes successfully (after about ten trials each... :S) The trick is to get aligned to the centerline as soon as possible, then glide smoothly to the near end of the runway, and finally flaring up to get a VS very near zero. I had usually about -2m/s at landing, what are yours?

And a very important tip: Do not forget the landing gear D: (XR alerts you though)
 

Urwumpe

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I aim for -1 m/s usually. I won't worry before in risk of exceeding -2.5 m/s.
 
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