Why should we use DLC?

[sopebird]

A rookie on F-14B.

 

Still confused why we need DLC(Direct Lift Control) during final approach?

 

The manual wrote: "DLC is used to control vertical glideslope position without pitch control inputs or engine throttle commands".

 

But I think we can just only use pitch trim, right?

 

Hope someone can explanate this.

 

Thank you!

[Scotch75]

The way I understand it is it gives you virtually instantaneous response and effect, rather than waiting for the engines to spool up or down then waiting for the glideslope response from the power change. Once you have trimmed for on-speed aoa, activated dlc and adjusted the power to hold glideslope, if you're slightly high - dlc to slightly raise the spoilers (more drag, less lift, plane starts to drop), once you intercept the ball, dlc (spoilers) back to neutral (less drag, increases lift so holds your previous set attitude and glideslope).

 

So I think of it as adjusting higher or lower of neutral instantaneously. I still need a lot more practice to get the feel and touch right.

 

Cheers!

[Whiskey11]

The Tomcat has a lot of lift.... and having control over fine tuning the flight path on the carrier trap is super important for safety and ease of landing. Having access to something like DLC is a MASSIVE help in controlling an aircraft that otherwise doesn't want to land when that slow. Frankly, I wish the Hornet had it for landing... SUPER handy.

[Victory205]

A rookie on F-14B.

 

Still confused why we need DLC(Direct Lift Control) during final approach?

 

The manual wrote: "DLC is used to control vertical glideslope position without pitch control inputs or engine throttle commands".

 

But I think we can just only use pitch trim, right?

 

Hope someone can explanate this.

 

Thank you!

 

https://forums.eagle.ru/showthread.php?t=235701

 

https://forums.eagle.ru/showthread.php?t=235301

[Larkis]

I think we use them cause pitching and throttlemovement change your AoA so you need to trimm afgain. Qhile DLC just push you up and down.

[sopebird]

I think we use them cause pitching and throttlemovement change your AoA so you need to trimm afgain. Qhile DLC just push you up and down.

 

Thank you! Very simple words to understand the point. I think I understood the design of DLC now.

Edited March 17, 2019 by sopebird

[sopebird]

https://forums.eagle.ru/showthread.php?t=235701

 

https://forums.eagle.ru/showthread.php?t=235301

 

Thank you sir! Your tutorials are the most detailed and professional ones yet. I read the two you posted. Still need some time and practice to get all you wrote. Thank you!

[sopebird]

The Tomcat has a lot of lift.... and having control over fine tuning the flight path on the carrier trap is super important for safety and ease of landing. Having access to something like DLC is a MASSIVE help in controlling an aircraft that otherwise doesn't want to land when that slow. Frankly, I wish the Hornet had it for landing... SUPER handy.

 

F-14B is a whole different story. Although I can get several on speed 3 wire recovery in tomcat with only 3-4 flight hours experience, I still have to struggle every time.

 

Hornet do not need things like DLC. It performed quite well with just throttle and trim adjustment. I can easily get on speed 3 wire carrier landings almost every time.

[Airhunter]

F-14B is a whole different story. Although I can get several on speed 3 wire recovery in tomcat with only 3-4 flight hours experience, I still have to struggle every time.

 

Hornet do not need things like DLC. It performed quite well with just throttle and trim adjustment. I can easily get on speed 3 wire carrier landings almost every time.

 

For sure, the workload is a lot higher and you are constantly working in the pattern. The turn onto the groove also takes a lot more finesse.

[Victory205]

That's as it should be. The Hornet was designed for kids and is easier to land.

 

There is a new system being tested called "magic carpet", it's already on the F35. It uses the flaps and slats to instantly produce or remove lift in concert with stick movement. You are basically employing Direct Lift Control in response to stick input. The first F35 carrier landing evolution had zero bolters.

 

In ten years, no one will remember how to fly... ;)

[Deano87]

In ten years, no one will remember how to fly... ;)

 

Already happened with civilian people tubes. :joystick:

[razorseal]

That's as it should be. The Hornet was designed for kids and is easier to land.

 

There is a new system being tested called "magic carpet", it's already on the F35. It uses the flaps and slats to instantly produce or remove lift in concert with stick movement. You are basically employing Direct Lift Control in response to stick input. The first F35 carrier landing evolution had zero bolters.

 

In ten years, no one will remember how to fly... ;)

 

in 10 years, I don't think anyone will know how to drive a car either LOL.

 

Pretty by the time my kids start driving cars (12 to 14 years) unless you're buying an old used car, they will all be auto driving lol

[sopebird]

That's as it should be. The Hornet was designed for kids and is easier to land.

In ten years, no one will remember how to fly... ;)

Hahaha~

Today's naval air guys will have no words to argue…

[sopebird]

I just practiced several case 1 landings using DLC. I have to say it's pretty handy! This is a smart design in tomcat.

 

DLC make tomcat a lot easier to land. I can now expect 3 wire almost every time.

 

When tuning DLC wheels, the velocity vector will move up and down slightly, which is quite easy to control aircraft flight path during landing. If just use trim and throttle like what we do in hornet, we will need so many corrections till touch down. Power change also make velocity vector move a lot.

 

Got this tech now!

 

Thank you guys!

[Airhunter]

That's as it should be. The Hornet was designed for kids and is easier to land.

 

There is a new system being tested called "magic carpet", it's already on the F35. It uses the flaps and slats to instantly produce or remove lift in concert with stick movement. You are basically employing Direct Lift Control in response to stick input. The first F35 carrier landing evolution had zero bolters.

 

In ten years, no one will remember how to fly... ;)

 

While true, the sole purpose of all this new tech is to increase combat effectiveness, ease of use and performance. No one "up the ranks" really cares about how much "fun" their pilots are having. :D

[VampireNZ]

That's as it should be. The Hornet was designed for kids and is easier to land.

 

There is a new system being tested called "magic carpet", it's already on the F35. It uses the flaps and slats to instantly produce or remove lift in concert with stick movement. You are basically employing Direct Lift Control in response to stick input. The first F35 carrier landing evolution had zero bolters.

 

In ten years, no one will remember how to fly... ;)

 

'New system' - this was used years ago on the L-1011 Tristar :thumbup:.

DLC engaged on approach and fwd/aft stick movement just applied analogue DLC spoiler up/down movement, no elevator actuation and no pitch changes. More 'comfy' for the passengers apparently.

[Holbeach]

Anyone with FSX 1011 Tristar, will be familiar with DLC, which was introduced before the F 14 came out and is the only airliner to ever use it.

 

 

..

[Victory205]

'New system' - this was used years ago on the L-1011 Tristar :thumbup:.

DLC engaged on approach and fwd/aft stick movement just applied analogue DLC spoiler up/down movement, no elevator actuation and no pitch changes. More 'comfy' for the passengers apparently.

 

Yeah, but the Tristar didn't have a tail hook... ;)

 

It isn't just FBW stuff that is a problem, it's automation as well. I have nothing against FBW, but it depends upon how it is implement. I favor throttles and controls that provide feedback. Airbus doesn't, Boeing does for example.

 

That said, we do have issues with guys coming from FBW backgrounds trying to fly natural stability aircraft, but the opposite is rarely and issue. We had a long time F16 pilot fail to upgrade to a DC9 series airliner, despite having had several extra sims and 32 landings in the actual aircraft. He just couldn't get the hang of flap management, trim and feel of what were heavy control pressures after coming from the nimble little Viper.

 

Had to be a handful to be sure, but he got fired nonetheless.

[VampireNZ]

Yeah, but the Tristar didn't have a tail hook... ;)

 

It isn't just FBW stuff that is a problem, it's automation as well. ...

 

No sir it did not! :pilotfly:

 

Also yes, that is an understatement given the current events in the 737 world:(. I would rather have a competent pilot identifying a stall and taking corrective action any day of the week, compared to stupid computer that has no idea what it is 'actually' doing and no concept of anything apart from it's own little world of 1's and 0's. As we say - sht in = sht out 100% of the time.

[jcdata]

Ground effect . Dump lift maintain G/S

 

Sent from my SM-N950U using Tapatalk

[sopebird]

While true, the sole purpose of all this new tech is to increase combat effectiveness, ease of use and performance. No one "up the ranks" really cares about how much "fun" their pilots are having. :D

 

Absolutely agree with you.

 

Imagine that you just finished hours of fight mission. You are already exhausted after focusing for so long time, a lot G pulls, several air-air refueling, even heavier. Then you still have to pay 120% attention to dangerous carrier landings, even worse in very bad weather condition or at night. Life will be easier and safer for navy pilots if their fighters are easy to fly.

 

But come back to what we discussed here, for pure feelings of flight, Victory205 is probably right.

[MRaza]

Once you have trimmed for on-speed aoa

 

What is meant by "on-speed aoa"?

[Scotch75]

What is meant by "on-speed aoa"?

When landing gear is deployed and landing mode is selected on the hud, a small E bracket will show on the hud which moves up and down relative to your attitude, airspeed and power. On downwind you want to maintain 600 feet agl with power, at the same time trim the nose up so the E bracket stabilises on your horizontal "hud wings". Once you achieve this, you are considered "on-speed", your AoA (angle of attack) is optimum for the arresting hook to trap a wire. You now adjust up and down with power, without changing attitude of the aircraft.

 

Hope this helps,

[Victory205]

Not the E Bracket. Use the AOA indicator and indexer! This isn't a Hornet.

[Scotch75]

Not the E Bracket. Use the AOA indicator and indexer! This isn't a Hornet.

There is a small E bracket on the hud though isn't there? Or have I been looking at something different lol...? I tend to use the AoA indexer though once turning base.