Fly By Wire landing

[cfarsr]

Fantastic job getting this out on time. Very interesting plane and looking forward to the training missions and campaign to come.

 

This is an observation and may not be a bug so with that said, the landings are easy and you need to come in hot (light craft around 180-190). On touchdown, the nose hangs and you actually have to stick forward.

 

Is this the FBW trying to hold the nose up?

[Charly_Owl]

Try landing with the FWB emergency mode and see the difference.

 

The Mirage lands with nose-up usually, as shown in this video

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[Zeus67]

The nose up on landing is an aero braking maneuver. Basically you are using the aircraft's wings as one massive airbrake. I still cannot master it. But you should try.

[Corrigan]

Fantastic job getting this out on time. Very interesting plane and looking forward to the training missions and campaign to come.

 

This is an observation and may not be a bug so with that said, the landings are easy and you need to come in hot (light craft around 180-190). On touchdown, the nose hangs and you actually have to stick forward.

 

Is this the FBW trying to hold the nose up?

 

180-190 kts is far too fast, as we concluded in some thread somewhere.

 

I also noticed that the nose stayed high even when completely hands-off. Bug or aerodynamic feature/FBW? I don't know!

[Azrayen]

180-190 kts is far too fast, as we concluded in some thread somewhere.

Agreed!!

It's more around 140kt. But most important: get your AoA right (around 14°, you have dedicated brackets in the HUD in APP mode) and the speed will "follow".

[Zeus67]

You have to "move" the seat up when in Approach mode (see the keyboard map for the key).

 

Up until the heading scale is near the top of the combiner glass. Otherwise you won't be able to see the runway due to the high AOA.

[cfarsr]

180-190 kts is far too fast, as we concluded in some thread somewhere.

 

I also noticed that the nose stayed high even when completely hands-off. Bug or aerodynamic feature/FBW? I don't know!

 

As suggested I turned fbw into emergency mode and it got interesting real fast.

 

After some practice I got the landing speed down to a smooth 140.

 

Brilliant

[Croaker47]

180-190 kts is far too fast, as we concluded in some thread somewhere.

 

I also noticed that the nose stayed high even when completely hands-off. Bug or aerodynamic feature/FBW? I don't know!

 

Well, the F-16 in old Allied Force aerobraked that way, and it was listed as a feature in the manual. Rotation speed isn't necessarily takeoff speed anyway, and FBW generally assumes that if you aren't touching it, that you want it to keep doing what it's doing. :thumbup:

[AnnaNass]

EVERY plane needs to be landed nose up! the nose gear cant handle the weights from nose landings. And the touch down speed.... around 140 - 150

[PiedDroit]

landing is easier than I expected, if you use the brackets on approach you'll get a nice aerobraking. getting to a stop is a bit more challenging as you might veer off the runway when applying wheel brakes (under 90kts).

Do you guys approach with airbrakes deployed?

[Nealius]

I'm having a lot of trouble maintaining that 14 degree AoA especially in the flare. I guess I'm too used to the F-16's system in BMS. I'm always smacking the deck at 15-17 degrees.

[rrohde]

Do you guys approach with airbrakes deployed?

 

Yep!

[PiedDroit]

I'm having a lot of trouble maintaining that 14 degree AoA especially in the flare. I guess I'm too used to the F-16's system in BMS. I'm always smacking the deck at 15-17 degrees.

I don't know, the flare is still a bit fuzzy in my head. I hope someone more knowledgeable will elaborate here.

On top of my head I'd say you reduce throttle too much (or too soon).

 

Yep!

:thumbup:

[Jansgi]

I think the 14 AOA is easy to hold during the approach. On the flare I pull the stick very gently and start easing the throttle smoothly. I usually end up retracting the throttle fully just as my main wheels touch down. IMO this plane atm is the easiest to land.

[Azrayen]

Do you guys approach with airbrakes deployed?

Usually not.

The delta wing is a good airbrake in itself ;)

[PiedDroit]

Usually not.

The delta wing is a good airbrake in itself ;)

ok, ok :D

[jojo]

Good video for landing:

 

 

Small flare, air brakes on touch down and aero braking.

[Voodooflies]

EVERY plane needs to be landed nose up! the nose gear cant handle the weights from nose landings. And the touch down speed.... around 140 - 150

 

Those are empirical values, those depend of course of the weight of the aircraft, the weather and other various factors.

 

Do you guys approach with airbrakes deployed?

 

I don't, I deploy the airbrakes once main wheels are on the ground.

[Farlander]

I do it by feel.. i come in with a steep glide approach (holding IAS 210), and just before threshold i level out to touchdown on the double lines practicly every time. With some practice it really isnt that hard to do presice engine-out landings.

[rrohde]

I don't, I deploy the airbrakes once main wheels are on the ground.

 

Going to practice this as well now.

[jaguara5]

Look at 14:00 and forward.

The pilot aligns the runway with the -2,5 deg. pitch line (which is missing now, hopefully Razbam will add it) and places the fpm on the runway threshold. As you can see, during the approach the fpm is above the aoa bracket, only during flare the airplane reduces speed (from 158 - 154 to 144 kts)

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Edited December 31, 2015 by jaguara5

[jojo]

Look at 14:00 and forward.

The pilot aligns the runway with the -2,5 deg. pitch line (which is missing now, hopefully Razbam will add it) and places the fpm on the runway threshold. As you can see, during the approach the fpm is above the aoa bracket, only during flare the airplane reduces speed (from 158 - 154 to 144 kts)

 

Approach speed depends on weight.

140kt for light aircraft (9t), 160kt for heavy aircraft (11t).

Touch down speed between 125kt and 145kt accordingly.

 

I don't know if the shot of landing Mirage match the HUD tape, but it happens to be a Mirage 2000 B with 3 tanks. My guess is it's heavy landing.

 

The good speed is when you're on glide slope, at 14deg AoA: >] -O- [<

 

But pilots don't perform text book landing each time.

Edited December 31, 2015 by jojo

[TomCatMucDe]

A question out of curiosity, when place the FPM between brackets and land, you always have the right speed i found. As you said empty 140 and heavy 160. Is this correct? I try to do it faster or slower i couldnt

[Buznee]

Fantastic job getting this out on time. Very interesting plane and looking forward to the training missions and campaign to come.

 

This is an observation and may not be a bug so with that said, the landings are easy and you need to come in hot (light craft around 180-190). On touchdown, the nose hangs and you actually have to stick forward.

 

Is this the FBW trying to hold the nose up?

 

Yes depending on the flight control laws. Most fly by wire aircraft use pitch attitude, angle of attack and/or load factor (G) control for the pitch axis. You can see that the aircraft autotrims itself in flight. This could be a pitch attitude hold function. When you land it will basically continue it's auto trim until it has no more aerodynamic authority and the nose will fall down. It is a good idea to lower the nose before you get too slow, if not the nose may come down quite hard. Also same goes for takeoff. If you command to rotate the nose up for takeoff and you don't have enough speed, the controls will go full hardover to try and get you there and you'll get an abrupt pitch up. It can be a little tricky.

Edited January 1, 2016 by Buznee

[Croaker47]

Yes depending on the flight control laws. Most fly by wire aircraft use pitch attitude, angle of attack and/or load factor (G) control for the pitch axis. You can see that the aircraft autotrims itself in flight. This could be a pitch attitude hold function. When you land it will basically continue it's auto trim until it has no more aerodynamic authority and the nose will fall down. It is a good idea to lower the nose before you get too slow, if not the nose may come down quite hard. Also same goes for takeoff. If you command to rotate the nose up for takeoff and you don't have enough speed, the controls will go full hardover to try and get you there and you'll get an abrupt pitch up. It can be a little tricky.

 

The abrupt FBW takeoff pitch, the bane of exhaust nozzles everywhere.

 

I remember my friend managed to taxi without breaking anything; I was so impressed. The fireball that came afterward impressed me far more. He had to check the recording he made to make sure I wasn't bs'ing him when I guessed off-hand what got him. :P