Landing flaps

[mtik00]

YEDIT. 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.

:idea: That makes so much sense. No wonder I crash sometimes. Now that I think about it, I believe that's in the flight manual... just one of those things I forgot. Thanks for reminding me!

[Maverick-X]

It is actually quite simple. Aim your vector at the beginning of the runway and try to get in at about 120-140kias depending on your load. This is suitable for most situations and isnt hard to do.

 

For a correct landing, you align yourself with the glidepath if you use ILS, or get to an altitude where you will get a -3° path (again use tvv on hud). The AoA is the angle between the Airflow and your wings, so if you pull up, you increase the AoA. (AoA is alpha / α)

 

The aircraft has a lift-coefficient C_A, and the lift/alpha C_Aα. C_A represents the Lift your aircraft generates and is a function of your altitude, speed and weight. C_Aα is the amount your Lift increases with increasing AoA. So lets say your altitude is const (air density doesnt vary that much while landing) and your weight is, too. So only variable is your speed. As your speed increases your AoA decreases as the lift has to stay the same ( C_a = C_aα(V) * α = const )

[GGTharos]

It's about finessing everything. You have to hit the correct altitude, speed and descent rate for a good landing.

 

Once you master this in a straight-in, you will learn what a good landing looks like, and then you can do the fancier landings like overhead, combat approaches etc.

 

The straight-in is very slow and not appreciated if there are many aircraft operating in the area (note however, that the straight-in is the only approach you should use if you're low fuel or damaged, or heavy).

 

The point is, with a straight-in you learn all the basics: Distance/Altitude/Speed combination (you want 300'/nm from the threshold, that is a checkpoint for correct glideslope - so 3000' at 10nm, 1500' at 5nm, 300' at 1nm). When you use a different type of approach, you still have to hit 300' at 1nm, with correct speed of course. So it's all about knowing what your landing looks like, and doing it the same way every time.

 

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.

[Harzach]

Pfunk, what does AoA refer to specifically?

 

Read this!

 

[PFunk1606688187]

It also helps to treat a stabilized approach as being staged. Trying to go from 200+ KIAS down to VREF with full landing configuration is an overwhelming task for someone and sloppy flying too. Reach configuration in stages, like reaching the gear down and MVR flaps speed (which I tend to do at once) and decide at what point of the approach to do that.

 

Landing isn't just about the long final, its about getting there too. You can avoid a 10 or 15 mile final by doing some of your configuring during a downwind or crosswind leg, then rolling onto a 5 mile final you only need to reach the VREF AOA while dropping final stage of flaps. Planning the approach is very helpful, and visualizing it ahead of time helps you keep your heads down work from getting out of sync with where your plane actually in in the outside world.

 

If you're not hurried trying to get into ideal landing config then its easier to fly well and work on your flare, keeping centre line, and in general being a more put together pilot.

 

In general, flying the typical 3 degree glideslope purely visually is more difficult than meeting most of the other criteria. Its not based on a single instrument so it takes an instrument scanflow to determine things, and of course is greatly helped by having TACAN for distance.

 

One thing thats always good is to do a normal visual approach now and then with your standby HUD switched on. Flying with no HUD references whatsoever is a good exercise and reinforces fundamentals like analog instrument scan-flow that are often missed when you're leaning on the magic "go here" birdie in your HUD.

 

And I'll say it again, read and understand Angle of Attack. Its like a miracle concept. Not knowing it is like not knowing about gravity in a physics class. I had a great PDF once, and I'll link it if I can find it.

Edited August 2, 2013 by P*Funk

[Hamblue]

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.

 

When you touched down you were a little too slow and forgot to flare.

Result is you hit pretty hard and almost broke the gear.

Come in the same as you did but slow down some and get the flaps deployed before lowering the landing gear. Then keep it above 130 knots until you're at the runway. Drop throttle and flare with the nose up more.

 

Any landing you can walk away from is good but if the crew chief gets to go home without repairing damage it's even better. :thumbup:

[camsr]

I was using the gear as a lazy speedbrake. :music_whistling:

Is it standard to deploy flaps first?

[PFunk1606688187]

It really depends on the airplane. Large aircraft like commercial airliners have many stage of flaps that you cycle through til you reach gear down stage then final flaps. Smaller aircraft often have fewer stages and often gear down happens when flaps down happens since smaller aircraft often can bleed speed faster owing to lower mass.

 

737 spoilers definitely don't bleed speed nearly as well as the A-10's. :P

 

There's nothing wrong with dropping speed significantly and then dropping flaps and gear at the same time. I often like to come down to about 180ish when settling on my final from a 230-250ish pattern speed (lest it takes years to fly a pattern) which allows you to drop gear and flaps, but gear can be lowered at a higher speed so often I drop gear first, then flaps but the time between the two actions is usually no more than a few seconds (this is for MVR flaps). I never set final flaps until I'm at or past the 5 mile final point, though I rarely fly much longer than a 10 mile final anyway.

 

Also note, that with the military style landings like the overhead break you're dropping 40% brakes, flaps and gear all at once usually since you're doing radical reductions in speed and altitude to land very quickly, so if this is permissible within the correct margins the lazier long landings can easily accommodate plenty of personal style in flap and gear deployment schedule.

 

For the flare, I usually start flaring at or near like 70ft radar provided I'm in a stabilized 3' glideslope with a slight reduction in power simultaneously to keep the ballooning down, but if you cut it too much your sink rate will stay higher and you can have a harder than desired landing.

[Hamblue]

I usually play multiplayer where targets tend to be a bit further out.

First thing I do after a mission and out of ammo is to hit the red button to jettison the racks. That will get you 5-10 knots more speed.

 

I like to be at around 17-20k altitude so when returning, set up an angle for a gradual descent to base. By the time I'm ready to approach speed is usually 320-350 knots. At 5 miles out, deploy the speed brakes and the landing flaps. The flaps deploy automatically at 190-180 kts retract the speed brake and lower the gear. Only small adjustments are needed from there to be at the correct speed when landing.

[Tracer2k]

didn't test this with the latest version, so im unsure if it works correct

 

but in this track my jet is completely empty and almost out of fuel, i came in as slow as possible and i think it turned out pretty good

Landing no load.trk

Edited August 3, 2013 by Tracer2k

[Dejjvid]

If you want to do really nice flares you should pitch up when you are above the threshold so the TVV is pointing at the end of the runway.

 

Reduce power when main wheels touch the ground and extend full SB.

 

There is a bunch load of videos on YouTube.

[camsr]

I took everyone's advice and did the correct landing procedure. Have a look at the trk for a zero vis landing. Got it on the first run-in also.

lucky.trk

[NullSpace]

Personally, I wouldn't recommend trying instrument landings until you're really comfortable with visuals (Maybe you are, and have been practicing them like crazy since last post. If true, disregard this comment :) )

 

What sort of an instrument approach were you using? I didn't see either your TACAN or your ILS on, but I saw you messing around with you CDU a bunch. I've heard that you can make "GPS" approaches with the CDU, is that what you were doing?

 

Comments, you seemed to touch down pretty long, didn't have tho whole runway. Also, at least in my viewing of the track you veered off the runway at the end of your landing rollout.

[camsr]

I was using the EGI and my previous flight course to calculate the 90 degree turn towards the airstrip. I couldn't find the taxiway at the end of the runway until I was right on it, maybe that didn't show well or the replay is borked(1.2.3 replay). The important part of the whole affair was keeping the engine up until aligned. If I didn't make it the first run-in, I could level off above the runway and visually grab the true runway heading for the second approach.

[PFunk1606688187]

Well my notes on that landing are as follows.

 

You were doing a zero vis landing with apparently no precision instrument assists other than a GPS waypoint. This is fine under most conditions except zero vis (assuming real life limitations). Even with ILS under those conditions you wouldn't be allowed to land in that airplane. That said, very nice job of guessing it.

 

You started your roll in to final at something like 7000 feet and around 15 nm if I recall correctly. At this distance you should be at 4500 feet to ensure you easily capture the 3 degree glideslope, and even then the roll in ought to be earlier for that alt since its good form to capture GS from below. You put yourself in the situation of having to descend very rapidly while also needing to kill all your speed in the final 10 miles. Its not ideal because you're fighting to hit a stabilized approach and your time to do it is running out.

 

Ideally you want to hit that glideslope already brought down to a manageable speed and maybe already at MVR flaps and gear down. A standard downwind->Base->final pattern would make this simpler, and even if you don't want to do it that way, you flew a right angle course for a while before rolling in on final so this is a de facto base leg anyway. Its best then to try and bring yourself into at least partial landing configuration before entering final and completing it in the first 1/2 to 3/4 of the final leg. This obviously slows down the whole approach but real landings are supposed to be slow ponderous affairs to keep things safe. The military has an alternative for faster landings, the overhead break, which will take you from 1500 feet at 300 knots and put you on the ground in about 60 seconds.

 

For the touchdown itself obviously your flare was hampered by the zero vis, but this isn't a normal situation, so that doesn't matter here. The rollout definitely could be improved. I noticed you applied max brakes which sadly I don't think is the right thing to do. The Anti-Skid in this sim has never worked properly for the A-10, at least far as I understand, and applying max brakes with it turned on creates a situation where the brakes are shut off by it automatically over and over. If you use the RCtrl-Enter control monitor while you're braking you can see this. It just goes apeshite and does a bad job of braking, also making use of differential braking all but useless for maintaining centreline.

 

Best method for using brakes in the rollout is to apply about 50% brakes with an analog input if you can find one on your stick or rudder pedals. If you don't have one you might try binding it to something that can act like one like a rotary or something or try tapping. 50% usually is near the max you can go without triggering anti skid and if it does its usually intermittent.

 

I didn't see you using any rudder to keep centreline either, but you said the end is possibly screwed up in this version. In either case rudder and/or differential braking can easily let you keep centreline. The real A-10s typically rollout to the full runway length when doing a flight landing and its mandatory to do so when returning with ordnance, so its permissible to let the speed bleed off on its own. The anti skid issue is still annoying, but using 50% brakes will stop you very quickly once you're below 50-60 knots ground speed, and if you have to stop sooner well you probably landed well long.

Edited August 10, 2013 by P*Funk

[roadrabbit]

:D I have tried not to get involved, but .............

 

When starting out to land any sim a/c, as it has been said elsewhere, take your time and do everything slowly and methodically so that you learn what the effects of each action are, and how to counter them if necessary. Trying to slow down from 300 knots plus close in (< 5 miles) and extend gear, speedbrake and flaps, with the right power settings is beyond most people when learning how to land.

 

As a recommendation to newbies: slow down to 200 kts at 10 miles out at 2,000 feet above airfield level (so check the airield altitude and adjust!) and fly level. You will be below the 3 deg idealised glidepath for the runway. At 8 miles out lower the gear and set 40% speedbrake - adjust power to maintain about 170 knots. At 7 miles out set flaps to MVR - they will extend.

 

With flaps set you should start descending at about 600 ft/min on the idealised glide-path. Continue approach allowing speed to decay slowly to about 140 knots. Adjust power to maintain. The AoA should now be 'in play' and you can now follow its commands. At 1,000 ft above runway (about 3 miles out) select Landing Flaps. This will require an increase in power to counter the incease in drag from the flaps. Maintain 140 knots.

 

The TVV on the HUD should be set on the beginning part of the landing zone (that part of the runway blackened by previous landing aircraft!) throughout this approach.

 

Take note of the visualised part of the runway between the nose of the aircraft and the landing zone. If you have followed accurately up to this point then the landing itself is easy. Just before the grey bit of the runway disappears under the nose, simultaneously close the thrust levers and gently raise the TVV to the far end of the blackened touch-down zone (NOT the end of the runway). This will/should equate to a height of about 10 ft above the runway. Maintain this attitude i.e. do nut pump the stick back and forwards trying for a 'greaser' landing. The aircraft will settle on to the main wheels quite quickly, and once on the ground LOWER THE NOSEWHEEL onto the runway - do NOT just 'let go' or push forward on the stick!

 

This method will give you consistently good landings in the correct touch-down area of the runway.

 

Once the nose-wheel is on the ground, keep straight with the rudder, apply full speed-brake, and apply wheel brakes as recommmended earlier in this thread. Do NOT apply the nose-wheel steering until almost at taxying speed.

 

Once you have mastered this approach you can begin to close in to the airfield on the approach, and make configuration and speed changes a lot tighter. You will also be able to do 'touch-and-go' landings!

 

These latter landings mean more circuits in a given time, so more practice in a given time.

 

After the nose-wheel has touched down, apply 50% power, reduce speedbrake to zero, then reduce flaps to MVR. Once stable, and tracking down the centre-line, apply full power. Rotate in the usual manner, but be aware that some nose-down trim will most likely be required.

 

Enjoy! :pilotfly:

Edited August 11, 2013 by roadrabbit
Clarification

[Hamblue]

Good info.

Don't know if you meant to make a new thread or extend the other one about landing flaps.

 

Also add that you should line up the HUD flight path marker with the point on the runway you want to touch down.

Also remember to trim. Landing is no exception.

 

Just FYI, the Power Setting to slow the plane down from 300+ knots 5 miles out with flaps etc. is Idle or just over.

<S>

[PFunk1606688187]

Also, its worth noting that you should know how to fly towards a touchdown zone without the TVV as this is often the first thing to go with any battle damage.

 

Basic principle is you pick a spot on the ground to fly towards and you do your best to keep it stationary in your HUD area in front of you. As you get closer everything else will continue to shift as its relative size increases visually but the touchdown zone will remain in the same place, even as it continues to get bigger as you get closer.

[roadrabbit]

:thumbup: Both the above replies in this thread contain good tips. My repy was aimed at the very first attempts at landing by those new to DCS and the A-10C, so I was trying to keep it as short as possible. Even so, it kinda runs away with itself ......... :D

 

Incidentally, I have been trying to lower Sochi-Adler runway 06, but without any luck. It stubbornly resists my attempts and the airfield altitude remains as it always was. Funny thing - I have yet to burst a tyre :smilewink:

 

I guess the problem previously reported earlier in this thread is either a bug, or some folks are just not flaring at all??????

[camsr]

The real A-10s typically rollout to the full runway length when doing a flight landing and its mandatory to do so when returning with ordnance, so its permissible to let the speed bleed off on its own. The anti skid issue is still annoying, but using 50% brakes will stop you very quickly once you're below 50-60 knots ground speed, and if you have to stop sooner well you probably landed well long.

 

I have been noticing that braking the hog is a crapshoot sometimes. It does the weirdest thing when taxi-ing off the runway, the CDU blips out for a second, big yellow warning on the CICU. The braking force must be tremendous on this plane! Overall it seems a bit high-centered.

[Jona33]

I have been noticing that braking the hog is a crapshoot sometimes. It does the weirdest thing when taxi-ing off the runway, the CDU blips out for a second, big yellow warning on the CICU. The braking force must be tremendous on this plane! Overall it seems a bit high-centered.

 

That's intentional, it was introduced as a feature a while back.

[Snoopy]

when taxi-ing off the runway, the CDU blips out for a second, big yellow warning on the CICU. The braking force must be tremendous on this plane! Overall it seems a bit high-centered.

 

It's the correct operation, the CDU is downloading flight data to the DTC.