Landing Light Pointing

Even the SU-25 light is straight.

Su-25A?

Not last time I looked...

I don't own any modern aircraft modules (apart from free Frogfoot obviously, which I don't fly anyway), but I can confirm that in MiG-15 and -21 forward visibility during landing flare is nonexistent, so sideways-pointing lights are the only logical design feature.

Now, whether it's that much needed on modern birds as well and whether the angle and range of the beam is modelled in DCS Su-27 correctly - I don't know (it MIGHT be somewhat off, based on example of L-39 lights).

Su-25A?

Not last time I looked...

SU-25T, absolutely. The 25A I'm pretty sure is a bug. They hardly point left at all to the point that if you didn't have the visible convergence of the two beams in front of the cockpit, you couldn't even tell. The SU-27 on the other hand doesn't light up the runway whatsoever. If you have pictures showing otherwise than please share them, but there are so many bugs in DCS that it's hard to know whats real and whats not.

Pictures are hard to find but in this one if the lights weren't straight you would see an obvious difference in brightness between the lights.

Here is another one where both lights appear equal, suggesting the camera is within both main beams, and this is far right of the left light.

Judging from what I see here, I'd say they were set to focus on a point more or less directly ahead of the aircraft. The one on the left wing is distinctly brighter than the one on the right wing. Same video at two different start points. The first is takeoff, the second landing:

BTW, just a fun video to watch in its entirety, too.

Here is a screen grab from the only video I could find showing the landing lights. This one has updated avionics evident by the much more modern HUD.

The right light is pointed slightly down either purposefully or just slightly misaligned (mechanics and aircraft aren't always 100% precise in the real world). Due to that the widest part of the beam is slightly closer on the right side making it look pointed slightly left. If you draw a straight line along the inside of the beam though they will converge basically dead center.

Same video at two different start points. The first is takeoff, the second landing:

lol, at first I though you found a video for the photo I had found, then I noticed the external tanks.

Try it now

Thanks, I honestly can't figure out how it isn't working.

Thanks, I honestly can't figure out how it isn't working.

The part that reads "?t=127" needs to be changed to ?start=127

So, unfortunately, it's not a straight copy/paste. So inside the YT brackets, you'd have: R-EkSaw1Fqw?start=127

Thanks, Fox One, for the Russian text. That was helpful. It told me exactly what to look for.

 

So turn on landing lights as you pass over the Outer Marker. After the runout, reposition the selector switch to taxi (lights) and head for the parking area. And that's what the switchology indicates as well. Three positions: Landing-Off-Taxi:

 

...

So now that I've read the next section in the manual, I'm a bit less confident that what we have is entirely correct. Fox One referenced the manual which addresses landing on a floodlit runway. The next section, however, addresses landing on a dark runway (non-floodlit):

4.23.4. Особенности посадки на ВПП, не освещенную прожекторами.

 

Посадка с фарами на ВПП, не освещенную прожекторами, более сложна и требует повышенного внимания летчика в определении высоты начала выравнивания и выдерживания.

 

После прохода ДПРМ, на высоте не менее 100 м включить фары. После прохода БПРМ самолёт должен планировать в точку выравнивания, в качестве которой служат входные огни ВПП.

 

С высоты 30-20 м перевести взгляд на землю, освещенную фарами, и все внимание сосредоточить на определении высоты начала выравнивания. Выравнивание самолёта и посадку производить аналогично посадке на ВПП, освещенную прожекторами.

I translate this as follows:

4.23.4 The particular issues associated with landing on a non-floodlit runway.

 

Landing on a runway with landing lights and no additional floodlight illumination is more complex and requires the increased concentration of the pilot in determining the height at which to initiate the transition.

 

After passing over the outer marker at a height of at least 100 meters, turn on the landing lights. After passing over the inner marker, the aircraft must fly down toward the transition point until the landing lights hit the runway.

 

At a height of 30-20 m, look toward the ground illuminated by the landing lights and focus on the height at which to initiate the transition. The transition of the aircraft and the landing is similar to that of landing on a floodlit runway.

My assumption was that there was no provision for this aircraft to land on a completely unlit runway. It's pretty clear, however, that that provision exists. That being the case, whatever the landing light configuration is, it should be lighting the runway on its own well enough to allow the pilot to transition. What we now have doesn't even come close.

This calls into question both the alignment of the two large landing lights and whether or not the taxi light is also lit during landing. The LANDING position could simply turn on all lights, while the TAXI position leaves one (the smaller taxi light) lit with the other two extinguished. It may be that the two "landing" lights also need to be pulled a bit more toward center.

(Don't you love how I'm vacillating back and forth on this?)

The part that reads "?t=127" needs to be changed to ?start=127

 

So, unfortunately, it's not a straight copy/paste. So inside the YT brackets, you'd have: R-EkSaw1Fqw?start=127

Odd. I tried that before after looking at your videos and tried again now and it doesn't seem to work.

This is what's there right now [YOUnotTUBE]

EDIT: Never mind I figured it out. Even though I was deleting the first part of the link, the whole link was still there (as you can tell by being able to click on the above).

..That being the case, whatever the landing light configuration is, it should be lighting the runway on its own well enough to allow the pilot to transition. What we now have doesn't even come close.

 

This calls into question both the alignment of the two large landing lights and whether or not the taxi light is also lit during landing. The LANDING position could simply turn on all lights, while the TAXI position leaves one (the smaller taxi light) lit with the other two extinguished. It may be that the two "landing" lights also need to be pulled a bit more toward center.

 

(Don't you love how I'm vacillating back and forth on this?)

The video from the SU-27 cockpit seemed to show pretty much exactly the same illumination as in game though, didn't look like any significant light was anywhere near the runway. Of course they were only landing a little after dark when it was still bright enough out and cameras are notoriously bad at capturing a dark scene as the human eye does.

I personally would be surprised if the taxi light was not on too because the only reason to have it off is if there is too high a load on the electrical system. For a plane with flight computers (does it have one), radar, lasers, HUD and other high power consumption devices, I would be astonished if it made any difference.

Unfortunately, all this back and fore arises when you can't just drive to the airport and power up an SU-27 to check. Nobody has a surplus one they aren't telling us about?:D

maybe if someone can ask on the russian side to see if theres a sme in the know on the particulars.

Judging from what I see here, I'd say they were set to focus on a point more or less directly ahead of the aircraft.

This still from your video is looking pretty much straight at the nose, and to me the lights don't seem to be symmetrical at all...

But if they aren't symmetrical, they are absolutely not pointed left since the left light is far brighter in that shot from straight ahead. More likely they just aren't perfectly positioned. Maybe the right light was knocked and it is pointing somewhat down or doesn't deploy properly?

The only view of how the lights are actually pointed is that one updated SU-25 in the night flight video, and they are mostly symmetrical there. But since the right light in that one is also slightly pointed down, maybe that is the actual way they are designed? Maybe so one light is lighting more of the runway during the flare, and the other once the nose wheel is on the ground.

This still from your video is looking pretty much straight at the nose, and to me the lights don't seem to be symmetrical at all...

It a matter of seeing what you expect to see. :) So either the landing lights point to th eright in the Su-25 or one is pointing further ahead down the runway than the other. Wish I had these parked in my backyard so I could run out and check.

Me too...