Convair Delta Wing Test

May be correct there Rick ...

But the X-3 has gear down available under 300kias, but tire contact and spin-up is constrained to 201 knots, the touchdown speed.

So, I see no issue with gear down at 220-250 for drag and landing config set up as long as the pilot understands tire spin-up constraints.
 
000rick000 said:
Gear limits would more likely be set based on tire speed. And likely, is not over 200. I imagine it was probably a very small margin for error. Those speeds are very high and it is doubtful that the gear used was specially designed. Likely had tight landing speed limits. I bet it's in the documentations somewhere..... Would have to go back and look.
Click to expand...

So far I've gone with that thinking... not jacks and metal but, rubber limits. After all - this is the 1950's.
I haven't dared deployed gear above about 190 KIAS - Just because of the drag - you already have that in bucket loads on the wings when you stick back. I've certainly been shy of putting the rubber on the ground at anything above 175'ish...Kiss the tarmac at 145'ish and you're a champ.

The thing really has to be thought through for landing and you really seriously want to make it as soft as you can; if you bring it in hot it's going to spit you out, melt your rubber and everything else that's horrible. I would agree with Rick and say upper limit on touchdown is most definitely no higher than 200 KIAS - and that's on the limit - because it screeches side to side with that huge great vertical stab at the whim of the cross wind, etc.

And then you're putting that early rubber technology through the extra long roll out until eventual stop.
Stopping a 777 is much, much easier;

but definitely no where near as fun.
 
See the Gear limits on the X-3 attached ....

I think big jets also have a much faster gear deployment than touchdown speeds.

Need the drag and time to get aircraft trimmed for landing configuration.
 

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Sorry guys, for the confusion on my part, I was thinking landing speed and takeoff speed limits! Not gear operation speed.... Duh! That's my misunderstanding! Gear Up/down speeds may be very limited by the type of gear doors and how the gear is extending into the air stream... Don't want to rip off those doors!
 
In the 747 normal max gear extension speed was 270 knots and could be left extended to 320 knots. Tire speed was for the 400 235 mph (204 knots) and for the -8 landing up to 260 mph. Sounds like a lot, but touch down at Mexico City max landing weight, 195 knots TAS over the fence, and add maybe little tailwind and there you are!!

Another tire speed issue was flying the twin engine Boeing 737-400 out of Denver. In a twin the climb gradient in case of the loss of one is the limiting factor, so we would use what was called "Improved Climb", in effect you raced down the runway, rotating at a high speed so that you had less drag once airborne. I think it was something like flap 5 takeoff and rotate at 192 knots??

Poor abused tires, not a lot of miles on them!
 
The xml sounds are really nice but is there a simple way to limit them to just the vc view. No big deal if not. Thanks.
 
bob407 said:
The xml sounds are really nice but is there a simple way to limit them to just the vc view. No big deal if not. Thanks.
Click to expand...

Just curious; what sim/version?

The xml sounds are limited to the VC view per the code, so I need more details about what views you have them, and not have them.

EDIT: Oooops! They are also heard in these views, just quieter. I'll see about changing volume.

0-External View
1-2D Cockpit View
2-Virtual Cockpit View
4-Map View -->

Each of the sound's volume is individually controlled. What in particular are you annoyed with, or all?

Thanks
 
Last edited:
Milton Shupe said:
Just curious; what sim/version?
The xml sounds are limited to the VC view per the code, so I need more details about what views you have them, and not have them.
EDIT: Oooops! They are also heard in these views, just quieter. I'll see about changing volume.

0-External View
1-2D Cockpit View
2-Virtual Cockpit View
4-Map View -->

Each of the sound's volume is individually controlled. What in particular are you annoyed with, or all?
Thanks
Click to expand...

I am running FSXA on Win7 64 bit. The vc and 2d cockpit view sounds are all fine, volume and every other way. In all other views (external, tower, top down, etc) the two sounds that are very noticeable are buffet, and gear wind to the point where you lose much realism effect. To me, in real world they would barely be heard if at all. Thanks again.
 
bob407 said:
I am running FSXA on Win7 64 bit. The vc and 2d cockpit view sounds are all fine, volume and every other way. In all other views (external, tower, top down, etc) the two sounds that are very noticeable are buffet, and gear wind to the point where you lose much realism effect. To me, in real world they would barely be heard if at all. Thanks again.
Click to expand...

I'll see if I can get those sounds lowered for non-VC views.
 
000rick000 said:
This is fantastic! Must make this the default!
Click to expand...

Thanks, but this is a shot in the dark based on a fuzzy photograph.
As you rightly pointed out, corrections to be made, colors and textures need matching,
lighting to be fixed.

A project to keep senior hands and mind busy.
 
Fuel Flow Pressure

I'm wondering what the fuel flow pressure should be.
The pressure gauge is measuring around 16 psi.?
 
Seahawk72s said:
I'm wondering what the fuel flow pressure should be.
The pressure gauge is measuring around 16 psi.?
Click to expand...

Fuel flow pressure can't be controlled in FSX.
You get some when running the fuel pumps with the engine off, you get some when the engine is running without fuel pumps and the engine start logic doesn't care about it at all.
There's no way to scale it to boot.
 
Combi gauge

The XF-92A uses a combined gauge borrowed from Jan's F-86.
The F-86 has fuel pressure registering at 40 psi. I compared aircraft.cfg's
but can not tell how they got the F-86 to register higher. I can appreciate
we are talking about a value for appearance sake, but it would be nice to show
a higher reading for the gauge and to shut off a low fuel pressure warning light.
 
SH72,

I show 16PSI when at idle in the XF-92A.
Fuel pressure is engine driven.

The air file table 545 controls the fuel pressure readout best I can determine.
There is a scalar available.
I see nothing in the cfg file to effect change.

Otherwise. you can change the fuel pressure warning light gauge parameter to designate when it should come on.
Mine reads like so:

<Value>(A:GENERAL ENG2 FUEL PRESSURE, psi) 15 &lt;</Value>

Change to maybe 12 like so:

<Value>(A:GENERAL ENG2 FUEL PRESSURE, psi) 12 &lt;</Value>
 
Milton Shupe said:
SH72,

I show 16PSI when at idle in the XF-92A.
Fuel pressure is engine driven.

The air file table 545 controls the fuel pressure readout best I can determine.
There is a scalar available.
I see nothing in the cfg file to effect change.

Otherwise. you can change the fuel pressure warning light gauge parameter to designate when it should come on.
Mine reads like so:

<Value>(A:GENERAL ENG2 FUEL PRESSURE, psi) 15 &lt;</Value>

Change to maybe 12 like so:

<Value>(A:GENERAL ENG2 FUEL PRESSURE, psi) 12 &lt;</Value>
Click to expand...




Thanks, adjusting the "fuel pressure limit" at table 545, got the pressure up into the green.
 
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