It seems more difficult to keep the nose up when the DCS F/A-18C touchdown

[Northwind]

Compared to the real life aircraft, it seems more difficult to keep the nose up when the DCS F/A-18C touchdown.Even at 300 lb fuel or less.

No external store, full flaps.

I know FM maybe not completed yet. Just in case, if the developer didn't notice this.

 

Two real life aircraft video links.

 

 

https://www.youtube.com/watch?v=rph3hw4Us1Y

Edited August 13, 2019 by Northwind

[5e EVC Chappy]

This called aerodynamic braking and it is not recommended for the F-18. It's a normal technic for the F-16 tough.

 

 

As per NATOPS manual:

 

7.3.3 Touchdown.

Maintain approach attitude and thrust setting to touchdown using the lens or make a firm touchdown at least 500 feet past the runway threshold. At touchdown, place the throttles to IDLE. The aircraft tends to align itself with the runway. Small rudder corrections (NWS) may be required to keep the aircraft tracking straight. Using a flared minimum descent rate landing, the WOW switch may not actuate immediately. In this case, the throttles cannot be reduced to ground idle and may be inadvertently left in the flight idle position, thereby reducing the deceleration rate and extending the length of the landing rollout. Track down the runway centerline using rudder pedals to steer the aircraft. Aerodynamic braking is not recommended. Getting the nosewheel on the deck and use of aft stick (programmed in by light braking and slowly pulling the stick aft after touchdown so only the minimum required distance to command full aft stabilator deflection by 100 knots) provides faster deceleration from the stabilators and more directional control with use of the NWS.

[Northwind]

Yes,Aerodynamic braking.Thanks for reminding me of this English word.

And I know it is not recommended.

But still thanks.

Edited August 13, 2019 by Northwind

[flavnet]

Aerodynamic braking is not recommended for aircraft carrier landings. I always do it when I land at airports. Just like you see on the videos. By the way, the best display for an F-18:

[bbrz]

It might be a bit more difficult, but not significant IMO.

Depending on the technique, the nosewheel drops just below 100kts onto the runway. This seems to be roughly in line with the -1 which mentions that full aft stick at 100kts is possible without lifting the nosewheel from the runway.

[Northwind]

This may be related to the position of the center of gravity, the force generated by the control surface, and the weight of the whole aircraft.

Of course, there may not be.

If so, it probably means that FM needs a lot of work.

If the center of gravity, the force generated by the control surface, or the weight of the whole aircraft have problem, the possible effect is on the entire FM.

Or maybe related to reverse ground effect.

Edited August 16, 2019 by Northwind

[104th_Money]

I do believe that this is more due to the actual position of the wheels. With weight on wheels they sit farther aft than other jets but the struts go forward then up, more in line where other jets have their struts in relation to the fuselage. So there is more weight in front of the pivot point and the control force isn't there at landing speed to overcome once the struts compress.

[Chuck_Henry]

I've found it's only really possible to truly flare the F/A-18 by leaving the throttles where they are for on-speed AOA as you flare, as opposed to going to idle over the threshold and trying to do it all with pitch. The reason being that you're already trimmed on-speed, so any attempt to arrest the descent rate using pitch alone will result in getting slower than on-speed, as well as a huge amount of induced drag. You're not going to be able to hold the nose off when you're bleeding energy like that.

 

A technique you could use is intentionally trimming faster than on-speed (maybe drop the gear and flaps, and don't even touch trim). That way, as you cross the threshold and go to idle, you'll be going from red chevron to amber donut in the flare, as opposed to amber donut to green chevron. EDIT: You can see this is what the Finnish F/A-18 does in that first video. Watch the AOA repeater on the nose strut. Totally red until completely in the flare, at which point it went to amber.

 

How much of this is accurate for the real Hornet and how much has to do with the STILL BUGGED reverse ground effect, I couldn't say, though. In any case, when I want to pop wheelies on the runway, I hop in the F-5E. It's basically an older, less powerful Hornet, anyway.

Edited August 15, 2019 by Chuck_Henry

[bbrz]

I've found it's only really possible to truly flare the F/A-18 by leaving the throttles where they are for on-speed AOA as you flare, as opposed to going to idle over the threshold and trying to do it all with pitch.

On most high performance jets you don't reduce thrust to idle over the threshold (if you fly with the correct approach speed plus minus a few knots).

 

Especially if you flare you need the thrust, since speed decreases during the flare, even without thrust reduction. As I've mention above, I don't see a siginficant difference in the DCS F/A-18.

 

Btw, I didn't notice the reverse ground effect in landing configuration. The sink rate noticable reduces in ground effect.

Edited August 16, 2019 by bbrz

[Chuck_Henry]

On most high performance jets you don't reduce thrust to idle over the threshold.

 

Especially if you flare you need the thrust since speed decreases during the flare, even without thrust reduction.

 

As I've mentioned above, I don't see a significant difference in the DCS F/A-18.

 

Btw, I didn't notice the reverse ground effect in landing configuration. The sink rate noticeably reduces in ground effect.

 

If you don't mind me asking, then, what's your technique when it comes to performing a flared landing in the F/A-18? I know the T-38 and F-5 have "crack-shift-idle-flare", both from reading the AF training pub on it and Mover's first video with the DCS F-5E.

 

I imagine you really have 2 options - land with power on the jet, or gradually increase thrust as you flare, then go to idle once you've arrested the descent rate without getting slow.

[bbrz]

The F-5 and the T-38 plain flaps don't produce a lot of drag and there are (at least) 3 different 'official' ways how to land the T-38.

 

In the F/A-18 it's just about keeping the energy into the flare. Once I've started the round out and I'm only a few feet above the runway I start reducing thrust.

 

Especially in the F/A-18 it is essential that you keep a bit of thrust through the actual touchdown, so that you can reduce the thrust to ground idle (same problem IRL).

 

Re-read your above post and I guess you ment 'decrease thrust as you flare'...

Edited August 16, 2019 by bbrz

[Chuck_Henry]

Re-read your above post and I guess you meant 'decrease thrust as you flare'...

 

I actually did mean increase, like just bumping a little power in as you flare and then taking it out so as not to get slow too soon (assuming you're flying the glidepath exactly at on-speed AOA).

[bbrz]

That's definitely not required since you do want to decrease the speed in the flare. Furthermore the ground effect is rather pronounced and noticeable reduces the sink rate. A thrust increase would decrease the sink rate even further.

[Fox One]

This called aerodynamic braking and it is not recommended for the F-18.

 

 

The flight manual says aerodynamic braking is not recommended. It doesn't say aerodynamic braking is not possible, even pulling the stick fully aft.

 

The first video link in this thread clearly shows IRL aerodynamic braking can be done nicely. However in DCS when landing with full flaps aerodynamic braking is not possible, even if you quickly pull the stick fully aft. Just not possible, even if you land with close to zero fuel and remove gun ammo. Obviously, in DCS F/A-18 there is still some stuff that is not accurate in the flight model.

 

However in the sim aerodynamic braking is possible if you land with HALF flaps. So the error in the flight model might be flaps related. With full flaps some data in the flight model is probably incorrect.

[bbrz]

However in DCS when landing with full flaps aerodynamic braking is not possible, even if you quickly pull the stick fully aft....However in the sim aerodynamic braking is possible if you land with HALF flaps.

Aerobraking works for me with full and half flaps (it is easier with half flaps). Don't forget that extending the airbrake also helps keeping the nose up.

Sink rate at touchdown must be minimal as well.

Clean with about 1000lbs fuel I can keep the nosewheel clear off the runway until ~100kts.

[Fox One]

Aerobraking works for me with full and half flaps (it is easier with half flaps). Don't forget that extending the airbrake also helps keeping the nose up.

Sink rate at touchdown must be minimal as well.

Clean with about 1000lbs fuel I can keep the nosewheel clear off the runway until ~100kts.

 

 

For me landing with full flaps after main wheels touchdown even with full aft stick the nose wheel touches the runway in 2-3 sec (even at minimum vertical speed at touchdown). Can you keep the nose wheel up longer? In the first video in this thread it's 6 seconds.

 

 

The airbrake I don't think it has any nose-up pitch effect in sim.

[bbrz]

For me landing with full flaps after main wheels touchdown even with full aft stick the nose wheel touches the runway in 2-3 sec (even at minimum vertical speed at touchdown). Can you keep the nose wheel up longer? In the first video in this thread it's 6 seconds.

The airbrake I don't think it has any nose-up pitch effect in sim.

Yes, more than 2-3sec. When do you reduce thrust to idle? If you e.g. touch down at idle thrust, speed will reduce rather quick and the nose will drop faster as well.

 

The speed brake does induce a slight pitch up moment in the sim. Maintain a 8deg pitch attitude at e.g. 120kts (maintain both) and extend the speed brake. The pitch attitude will start to increase.

[Northwind]

In the first video,the Finnish F/A-18C does not need speed brake to keep the nose wheel up.

[bbrz]

In the first video,the Finnish F/A-18C does not need speed brake to keep the nose wheel up.

? 3sec after touchdown the speedbrakes extends...

[Hyundae]

I do believe that this is more due to the actual position of the wheels. With weight on wheels they sit farther aft than other jets but the struts go forward then up, more in line where other jets have their struts in relation to the fuselage. So there is more weight in front of the pivot point and the control force isn't there at landing speed to overcome once the struts compress.

I agree 100% with the comments above.

The hornet landing gear structure makes the front heavy after touchdown.

And this feature is well implemented in the dcs hornet.

Edited August 17, 2019 by Hyundae

[Northwind]

? 3sec after touchdown the speedbrakes extends...

Before that,the Finnish F/A-18C already keep nose wheel up.

[bbrz]

The slower you get, the more difficult it is to keep the nose up. Hence you don't need the speedbrake immediately at/after touchdown.

[CBStu]

When I got the Hornet a while back my main focus was carrier traps. I am OK at straight-in but still lousy at doing a correct pattern so I will keep at it. When I tried landing on land I had problems there too. So I just do carrier traps on land also and they work pretty well. Takes a while to get the power for glide slope and stick for lineup, but it works. I have read a couple of threads about the weak braking and agree, sure seems weak to me. But then I started hitting the air brake as soon as the wheels hit. That helps. In the last week I saw again, the recommendation to pull the stick fully to the rear. What do you know that helps too. For me anyway, on speed AOA landings work everywhere even if they aren't normal in RL.

[dramabeats]

When I got the Hornet a while back my main focus was carrier traps. I am OK at straight-in but still lousy at doing a correct pattern so I will keep at it. When I tried landing on land I had problems there too. So I just do carrier traps on land also and they work pretty well. Takes a while to get the power for glide slope and stick for lineup, but it works. I have read a couple of threads about the weak braking and agree, sure seems weak to me. But then I started hitting the air brake as soon as the wheels hit. That helps. In the last week I saw again, the recommendation to pull the stick fully to the rear. What do you know that helps too. For me anyway, on speed AOA landings work everywhere even if they aren't normal in RL.

 

You won't find many US Hornets flairing on land

 

Flying on speed AOA until touchdown is the normal technique

[med-taha]

 

2 f/a-18 rhino flaring