Landing flaps

[camsr]

Sometimes the flaps don't go down, but I still find it easy to make a not so rough landing with the speedbrake. Why don't the flaps come down?

[St3v3f]

You're too fast

[Mike Busutil]

Make sure the flaps are set to "MVR". (Maneuver) this will allow the flaps to extend and retract on their own based on your airspeed...

[Evil.Bonsai]

Make sure the flaps are set to "MVR". (Maneuver) this will allow the flaps to extend and retract on their own based on your airspeed...

 

They do that in either the MVR or DN position. You want DN for landing and MVR for takeoff.

[cichlidfan]

You're too fast

 

To clarify...

 

From the Flight Manual pg 105

 

If airspeed exceeds 185 KIAS, the flaps cannot be extended. If the flaps are extended and the aircraft reaches 185 KIAS or greater, the flaps will automatically retract to the UP position. In such a situation, the flaps will extend to their previous position if the aircraft decelerates below 185 KIAS.

[PFunk1606688187]

Its perfectly possible to land the Warthog without any flaps at all (see battle damage and loss of hydraulic system) but even then the correct landing speeds would be well below the 185 KIAS to allow flap extension.

 

Make sure you use ~40% speedbrakes if you're having issues bleeding speed ahead of your landing, and until you're some badass who can put it down wherever he wants take at least a 5 mile final to get lined up and configured.

[camsr]

The flaps go down automatically when slowing?

[NullSpace]

The flaps go down automatically when slowing?

 

Not exactly. To reiterate what's been said already: If you have the flaps set to MVR or DN, and you go above 185, then they'll auto-retract. If you leave the switch for the flaps where it is, they'll go back out to wherever you have the switch set to when your airspeed drops below 185 knots.

 

In short, at KIAS < 185, flap position = switch position, at KIAS > 185 flap position = up.

 

Does that clarify?

[camsr]

Yeah, it just seems different. What happens if the airspeed indicator is busted?

[camsr]

You're too fast

 

I have found it easier to control the glide in by deaccelerating quickly until the runway. I don't know why the training mission says to maintain 120kts, that's just wrong. But every time I come in I am way above glide slope speed, until the runway.

Edited August 2, 2013 by camsr

[NullSpace]

About 120 knots should be the correct Vref for an A-10C, though it varies a bit with fuel load and stores carried (Someone correct me if I'm wrong). The glide path you're shooting for would be 3 degrees, so put the TVV between the -5 pitch line and the horizon line, a little closer to the -5 line.

 

I'm not sure what happens if your ASI dies. Assuming that you've actually lost your airspeed and not just the HUD or such, I would assume that they would extend. As we're mentioning damage, keep in mind that if you lose your left hydraulics, you will lose control of your flaps. However, when losing hydraulic pressure they extend, so I doubt that's your problem.

 

Again, what speed are you approaching the runway at, if you're above 185kts, flaps will be up.

[St3v3f]

You 'can' land in many ways, and the A-10 can indeed endure quite a lot of bad treatment. However, if you want to make it a good landing, you want to get configured at around the outer marker.

That means flaps down, gear down, speedbrakes ~ 40%

Aim the TVV for the treshold at -3°

Your speed depends on your weight, so that you see the donut

Keep that until you flare, retard the throttle and touch down. Open speedbrakes fully and brake carefully

[camsr]

Is this a good landing? I usually glide in at a steeper angle and carefully use speedbrakes to get to 140kias, to keep the touchdown lighter.

a10c landing.trk

[159th_Viper]

Speed is largely irrelevant: 3 degree glide slope with a green doughnut - if not then you're doing it wrong.

[ralfidude]

I need to test this, but i think i have been able to drop the flaps down with the speed indicator busted after i dropped my gear down.

 

So without the gear down, the flaps wont go down above 185, but with the gear down it might force the flaps down if you set your flaps switch to mvr or down. Don't take my word on that one though. I might be paranoid. In fact I'm twitching right now a little...

[St3v3f]

Speed is largely irrelevant: 3 degree glide slope with a green doughnut - if not then you're doing it wrong.

 

Speed, weight and AoA are directly tied together, so the donut reflects the 'correct' speed of the aircraft, depending on its weight.

[camsr]

Speed, weight and AoA are directly tied together, so the donut reflects the 'correct' speed of the aircraft, depending on its weight.

 

Does the speed remains constant in the glide?

[159th_Viper]

Does the speed remains constant in the glide?

 

Fly the green doughnut and see for yourself. All depends on your landing configuration. As I said, forget about speed - the doughnut will ensure your speed, whatever it might be, is correct.

[camsr]

Okay I did it and all went well, I was even able to put it down on autopilot :)

It was different gliding in, and took a lot longer. I assume doing it this way only works if you get on the glide slope with the correct speed.

[PFunk1606688187]

The doughnut represents 19-21 units of AOA which can be seen on the AOA indicator. This is the normal landing AOA regardless of weight. This will produce the correct landing speed regardless of weight or even power setting (within reason).

 

So you set the AOA for the doughnut, trim it to stay that way, then adjust your sink rate with the throttle.

 

Correct sink rate for a particular speed will produce a loss of 300 feet for every 1 nm traveled if you want the 3 degree glide slope. Easiest way to maintain the correct sink rate though is to put the TVV on the touchdown zone and keep your sink rate so that the TVV sits at -3 degrees.

 

Its a very simple method when you get used to it, and saves a lot of faffing about with speeds and nonsense.

 

EDIT. If you're not on the correct glideslope you can still use the correct AOA, you just have to use more power for the shallower descent. AOA and its resulting speed should remain constant when trimmed while power/throttle only alters the sink rate (as long as you don't firewall it).

Edited August 2, 2013 by P*Funk

[camsr]

So it's all about throttle finesse then. I think I found it easier before to use the speedbrake, and just cut the throttle, but many times I did overshoot the runway. I guess I will practice more, thanks.

[PFunk1606688187]

Yea, its really all about managing the various inputs to generate the stabilized approach. The rule is as always:

 

Pitch for speed, power for sink rate

 

I did that but it never truly clicked until I comprehended the concept of Angle of Attack. If you can understand that then knowing what you're telling your plane to do during landing (as well as any other stage of flight) suddenly makes a lot more sense.

 

EDIT. Also, the speedbrakes are only really needed on landing to create enough drag to force you to keep your power high so that you don't have to spool them up during a go around. Having idle throttle during landing is very dangerous. Just look at the recent 777 crash at San Fran.

[NullSpace]

camsr, I think one aspect of this is that the way you've been doing your landings actually makes it HARDER on yourself to perform. It will take a bit of time to get the hang of, as PFunk said, Pitch for speed, power for sink rate, but once you do, the whole process is much easier.

 

You don't need correct your speed and such with the brakes at the last minute, instead you have plenty of time to get lined up and at the right speed and sink rate. That makes it easier when landings are more complicated (i.e. ILS, engine damage, high crosswind, etc.)

[camsr]

Pfunk, what does AoA refer to specifically?

[PFunk1606688187]

Angle of Attack