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Indexer, E bracket and FLOLS.


Crash

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I would like to know how to correct my flightpath using the above. Is there any good videos showing what to do if the indexer is red? Do I reduce throttle, trim up, pitch up? The vector on the E bracket seems to move in different directions and the FLOLS doesnt seem to match what I think the plane needs. All help appreciated.

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AOA Indexer - 3 positions. 

Upper chevron is green.  This lights when you are fast.

Middle doughnut is orange.  This indicates "on speed".

Lower chevron is red.  This lights when you are slow.

You can see in the opening screen that both the green and orange are lit.  This means he's either on speed, getting fast, or fast, slowing to on speed.

The E Bracket is another AOA indicator.  The circle with three lines to the right is the velocity vector indicator.  This is where the jet is actually going, regardless of nose position, and, if it's over the ground, will indicate the spot where the jet will eventually hit the ground if nothing is changed.  Note that the position of the velocity vector on the E bracket is is above center, quite high on the indicator.  This coincides with the "slightly fast" indication given by the AOA indexer to the left as previously described.

Being a Tomcat type, I can't help you with FLOLS, as I have no idea what it is.

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  • 1. DDz Quorum

Wrong way round Kira; 

Green chevron = too slow either add power, drop the nose slightly or a bit of both.

Yellow donut: at target AoA. 

Red chevron = too fast, either reduce power or raise the nose or a bit of both. 

But that's only half the story. Being at the right AoA doesn't mean you have the right glideslope. You need to ensure that you're stable "on speed" with your nose pointed ~5 degrees above the horizon; because "on speed" is ~8 degrees AoA this will give you your glideslope of ~3 degrees.

However, even getting these 2 right does not equal a successful trap as you may well be "on speed" and holding the right glideslope but if you don't finish your turn onto the groove at exactly the right distance and altitude from the carrier you will find yourself either too high (and thus overshooting the wires) or too low (and undershooting).

This is where the FLOLS comes in. It will tell you if you're too high low and even give you hints as to if you have your glideslope and trim dialled in correctly. If the yellow light (meatball) is above the green datum lights, then you're high and will have to correct with a brief reduction in RPM. If low you'll need to increase your power temporarily to translate your glideslope up to meet the optimum. 

The tricky part here is that a change in throttle has an immediate effect on your AoA; it's easy to make a power correction too large or for too long and overshoot the target glideslope, particularly when cutting power as engine spool up times are longer than spool down and increasing AoA = increased drag. All this means that the aircraft is slower to power out of a "slow" or "low" position than it is to brake from a fast or high.

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Don't know how much this will help you or not Crash,

 

Although its in an F16, the same principles apply. You can see I put the velocity vector onto the area of the runway I want to land on, as I come out of the turn. Initially I'm to fast, so I chop the throttle, and as the speed bleeds of I slowly raise the nose, increasing the AoA but so that the velocity vector remains on the end of the runway.

Once the E bracket is in the middle of the velocity vector and that is still on the end of the runway, it is then simply a case of modulating the throttle to keep it all there, which will hold you on speed (in this case for an F16 @155 kn).

You don't flare modern jets, but fly them onto the ground on speed and on AoA.

As Tom has alluded to, the FLOLS is additional information to tell you whether above or below the glide slope. Above it chop power until on it maintaining AoA, below increase throttle doing the same until on it.

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  • 1. DDz Quorum

That stuff is not needed really.

Yesterday I somehow landed the Tomcat on the carrier, third wire, when it was dark, and I did not even have any instrument lighting on ... lol

FFB stick is nice though, you can feel it in that way....

The Three Toms (Fen, Brems and AP - 2x Cat, 1x Hornet) with their fancy approach paths and  flols and fpv and procedures all landed successfully before I did,  and none of them got third wire!  Mind you, they landed before I did, so it was even lighter for them!

Yeah, I guess I got lucky with third wire' n' all, and it'll surely never happen again ... :shaunv2:

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On 5/31/2021 at 7:44 PM, Bremspropeller said:

The F-16 should normally be flared, as the landing-gear isn't designed up to Navy-specs.

I always thought so to, but I remember watching a Wags video when it first came out saying fly it on to the runway on AoA on speed.

Certainly in DCS you can, lol.

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Well, looking at your boresight-cross and watching that AoA Indexer shallow out, you actually do flare - it might happen subconsciously, though. 😃

I have heard there are two techniques used by pilots:

One technique is to fly 13 Units AoA down the approach right to touchdown (your sinkrate is dependant on power here, so giving it a burst of power will practically "flare" the aircraft). The downside of this technique is that the nozzle will touch the runway at 15°, so there's very little of a margin.

The other technique is approaching slightly fast (FPM at the top end of the E-bracket), which is 11 Units. Or is it actually degrees in the Viper? You'll bring that up to 13 Units/degrees in the flare, synchronized with placing the FPM at the far end of the runway. I'm using this technique as it seems more natural to me.

There seems to be some sort of ground-effect modelled in DCS, which will cushion your sinkrate a bit. As it does IRL.

 

FPM = Flight Path Marker.

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