Altitude based trigger problem

[Spetz]

I've been trying to get a trigger working for mission but its giving me grief. I want a trigger based on an altitude of anything higher than 3045 meters ( roughly 10,000 feet). I have it working at 5000 feet but it will not work at the higher level.

 

This is what I have..

 

ONCE > UNITS ALTITUDE HIGHER THAN (test pilot,3045) > MESSAGE TO ALL

.......... UNIT INSIDE ZONE (test pilot, Mvr message)

 

It's the exact same at the lower altitude except the altitude obviously and a different zone, and it works.

 

Does pressure altitude come into effect with this type of trigger? I've set it to 29.82 as ATC directed on the ground. I did notice when I air start its set at 29.92, 200 foot difference. All other triggers in the mission work fine.

 

No trigger zones are touching each other to be safe.

 

Any ideas?

 

Oops, wrong area..can a mod move this for me. Thanks

Edited February 19, 2013 by Spetz

[Speed]

Without the mission, I can only guess that maybe you misnamed a unit or a zone.

[Spetz]

Think I figured it out.

 

When you are on the airfield, ATC gives you QFE, which is different at each airfield. You set that into your altimeter (shoudl read Zero height) and take-off. Once you are airborne, that QFE is useless, you have to redo your altimeter to the pressure levels in the area, which unless you have an ATIS report for everywhere you are flying, it's impossibe to get. Once above 18,000 feet, you set it to 29.92..all is good..

 

But is seems the ME takes into effect all the differing pressure areas.

 

You can test this out easily. In the A10, level out and use ALT/BRG hold at 5000 indicated on the HUD. Your altimeter should read the same despite whatever setting you have. Switch to F2, and you can see you actual height MSL, which can vary by hundreds of feet. By moving your altimeter knob up and down you can level out the F2 altitude and the indicated altitude. Once they read the same, that is the altimeter setting for that exact spot..

 

My issue was that STPT 1 was only 4nm from the airfield, so the QFE worked just fine on that trigger zone because it was so close. But once I fly to STPT 2 and 5000 feet higher, the altimeter was way off, even using 29.92 at 10,000 feet was several hundred feet difference, almost 800 IIRC.

 

So basically, unless you can get an accurate reading and equal reading, it is rather hard to make a higher than / lower than trigger, especially using dynamic weather..

 

Anyway, this is what I'm thinking... Sounds right to me..

[Speed]

Think I figured it out.

 

When you are on the airfield, ATC gives you QFE, which is different at each airfield. You set that into your altimeter (shoudl read Zero height) and take-off. Once you are airborne, that QFE is useless, you have to redo your altimeter to the pressure levels in the area, which unless you have an ATIS report for everywhere you are flying, it's impossibe to get. Once above 18,000 feet, you set it to 29.92..all is good..

 

But is seems the ME takes into effect all the differing pressure areas.

 

You can test this out easily. In the A10, level out and use ALT/BRG hold at 5000 indicated on the HUD. Your altimeter should read the same despite whatever setting you have. Switch to F2, and you can see you actual height MSL, which can vary by hundreds of feet. By moving your altimeter knob up and down you can level out the F2 altitude and the indicated altitude. Once they read the same, that is the altimeter setting for that exact spot..

 

My issue was that STPT 1 was only 4nm from the airfield, so the QFE worked just fine on that trigger zone because it was so close. But once I fly to STPT 2 and 5000 feet higher, the altimeter was way off, even using 29.92 at 10,000 feet was several hundred feet difference, almost 800 IIRC.

 

So basically, unless you can get an accurate reading and equal reading, it is rather hard to make a higher than / lower than trigger, especially using dynamic weather..

 

Anyway, this is what I'm thinking... Sounds right to me..

 

No, altitudes are not dependent in pressure in the ME- your altitude is just the your aircraft's y coordinate (assuming you're in "Vec3" coordinates).

[Spetz]

Well, if altitudes are not dependent on pressure levels, how does one set a ALTITUDE HIGHER THAN 3045(m) and have it trigger on the altitude displayed on you HUD? From every test I've done, it triggers it on the altitude displayed in the F2 view, not the HUD, which can be several 100 feet different?

 

Mission attached.. Altitude triggers are at STPT 1 and 2.

 

 

EDIT*** Figured it out. Mission editor uses 29.92 Hg for all altitudes on the triggers. Just have to set 29.92 after take-off to reach same altitude as what I set the ME to. Not the most realistic I guess, but works. Don't know why it didn't work before..

Edited February 20, 2013 by Spetz