Questions about real L-39

Real L-39 pilots tried DCS during this airshow and I think their opinion are more accurate than mine, I know how to fly in closed patrol ( 2nd solo and slot in virtual Patrouille de France), but I think airbrakes are really missing efficiency :music_whistling:

I understoud how gave his opinion and took a look who you are yesterday, but thx for the quick CV ... I was just giving my opinion ...

Flaps actually retract at exactly 320km/h airspeed (in RL). It can be +/- 1 in some aircraft.

Landing gear can´t be retracted when on the ground, because a small micro in the front gear leg won´t allow this to happen.

Also, airbrakes should auto deploy at M = 0.72. Does anyone has tested this?

I have DCS L-39 but right now I´m kind of bussy.:D

For the gears i tested

Flaps actually retract at exactly 320km/h airspeed (in RL). It can be +/- 1 in some aircraft.

 

Landing gear can´t be retracted when on the ground, because a small micro in the front gear leg won´t allow this to happen.

 

Also, airbrakes should auto deploy at M = 0.72. Does anyone has tested this?

 

I have DCS L-39 but right now I´m kind of bussy.:D

The mirco switch on the front gear does several things i dont remember them all but it turns off the weapon system on ground ... If interesting someone i can check documents...

The flaps have a switch too that bypass the rt-12 system ...

Some may ask why bypass a system that may save your engine from overheating ...

You will not like to have idle RPM when taking off (on final) so that system is bypassed when flaps are out ..

In the flight procedure the pilot have to check the two temperatures lamp on the master panel before retracting them ...

I know that the airbrakes are very effective in the l39 but i know that that plane have a very big inertia, and flying in a patrol with it need a very good sense of anticipation

Someone who flew this bird for many years told (in the Russian forum) that the air breaks are effective only with the speeds above 350 km/h.

Totally agree less speed less effect

Someone who flew this bird for many years told (in the Russian forum) that the air breaks are effective only with the speeds above 350 km/h.

Thank you for this information, real pilots i met and test L39 in DCS fly in patrol between 400 and 600 Km/h. I think their opinion is good, maybe missing sensation in simulator :smilewink:

Hello, I have a question regarding the VD-20 barometric altimeter.

Indexes "1" and "2" appear to show MSL altitude when the QFE is set so runway altitude shows "0", but this value is affected by the QFE setting and then becomes inaccurate. Value shown is 810m and actual value is supposed to be 952m. Setting QFE to 75.99 gets this much closer to the proper number, but then the runway runway zero setting is off.

This is what I never can understand about QFE in DCS. That scale for MSL should show the proper altitude number when runway is set to zero. The QFE knob should correctly adjust both of these indexes. It does not, or the outer indexes use improper math code.

Here is what the manual says about this index (and I'm calling BS):

5. Pressure correction indexes, for landing at high altitude airfields, where pressure is less than 670 mmHg. The indexes are moved by the knob.

I am guessing this is another fundamental bug of DCS(?)

It when your airfield has a preassure less or more than what can be introduced

Yes, I understand that and can see it work at Groom Lake as it goes off the scale there. I'll point out why it is wrong in the future.

My friend, for the record, you just paraphrased the manual. ;)

I want to apologize for going OT. My comment about the what the manual says is not about the real L-39.

What I would like to know:

It seems like these secondary scales are a readout of MSL altitude when QFE is set to 0 to match an airfield. Is this correct in the actual VD-20?

If it is true, and the numbers are off, it might be something fixable and that will be addressed in another post.

Hello, I have a question regarding the VD-20 barometric altimeter.

 

 

Indexes "1" and "2" appear to show MSL altitude when the QFE is set so runway altitude shows "0", but this value is affected by the QFE setting and then becomes inaccurate. Value shown is 810m and actual value is supposed to be 952m. Setting QFE to 75.99 gets this much closer to the proper number, but then the runway runway zero setting is off.

 

This is what I never can understand about QFE in DCS. That scale for MSL should show the proper altitude number when runway is set to zero. The QFE knob should correctly adjust both of these indexes. It does not, or the outer indexes use improper math code.

 

Here is what the manual says about this index (and I'm calling BS):

 

5. Pressure correction indexes, for landing at high altitude airfields, where pressure is less than 670 mmHg. The indexes are moved by the knob.

 

I am guessing this is another fundamental bug of DCS(?)

I think I figured it out. The index pointers are showing the pressure altitude above indicated altitude at given altimeter setting. At QNE setting your pressure altitude is 0m above indicated altitude and at QFE you are field pressure altitude above indicated. To get QNE indications would dial in the pressure altitude at the airport (not elevation!).

What you want is someone on the ground with a 760mm Hg-set altimeter to radio you and say "pressure altitude on the field surface is X meters." And then you crank the dial below the 670 mm Hg setting until the indices read X meter. If QFE setting is within the scale then he would just give you QFE numbers instead.

It's basically a way to set QFE when off the bottom of the scale accurately if you know the pressure altitude at airport surface. Unfortunately in DCS no one will give you this information.

Verify it for yourself. Go to any airport at any pressure weather and set altimeter to 760mm Hg. Remember indicated altitude on big hands. Now dial back altimeter knob until indices read your remember altitude. Big hands should be at 0m.

Thanks Fred, I forgot all about this post. I'll give this a try soon.

I do note the ATC at Groom AFB in the NTTR reports a correct QFE setting. I think it is the only NTTR ATC that works (and it doesn't officially exist) :)