Full Up Elevator during Cat Launches

In many videos showing the Tomcat taking off from a carrier I noticed that during the 2 - 3 second launch the pilot is gradually pulling the stick so that the elevators are pretty much fully deflected the moment when wheels leave the deck. If we do it in DCS we end up pretty much stalling the aircraft and usually with a 60+ degree nose up. Is this realistic?

If the pilot let the stick move freely during the cat shot, which is what a lot of guys did, then the bob weight system and the inertia of the stick itself would allow the stabs to go the full TEU position. However, as soon as the acceleration of the Cat stopped, the stab would immediately go back to the takeoff trim position, resulting in a normal rotation and fly away. In other words, when it came time to rotate, the stick wasn't full aft. If you hold the stick full aft, you'll get an extreme pitch up. Duh.

I held onto the stick with my elbow against my hip- I wanted to know where that sucker was, and didn't think that the old school technique of letting the stick come into your open, braced hand made any sense at all. The cat shot wasn't that violent on the big deck ships. You'll see a lot of guys do that on launch as well. If the stick was held full aft, then yes indeed, the nose would continue to pitch up.

I've seen a tail slide off of the cat during CQ, it was magnificent, and superior pilot skills, centering the stick and rolling with rudder, saved the day. The pilot unloaded, got some knots, and recovered before hitting the water. This was in an F14A. Exactly what is modeled by Heatblur.

Wow! Thanks for your answer!

However, I'm not asking why the stabs are fully up (stick pulled back). I'm asking why is such stabiliser position causing me to go nearly vertical in DCS when none of this happens in the videos?

To simulate the inertia stab movement during cat acceleration I tried creating this deflection manually but no matter how quickly I centre the stick/stabs after my gear leaves the deck I end up looking up into the sky instead of only achieving a ~30-degree pitch up..

you need to push it forward of center and gradually release as the nose comes down... if you practice FCLP touch and go's with full flaps you have to do the same thing as you leave the runway because of all the nose-up trim

Damn, I want to believe what you're saying but none of that forward stick pushing is ever seen in the videos:

They just pull (or inertia does its work), roll off the deck and centre with a nice 30-degree climb occurring next.

You might also need to look at your trim indicator prior to launch....I usually give it some nose down especially if I'm tanks only....you definitely shouldn't be shooting up to 30 deg.... remember you're not supposed to exceed 500' on the fly out to 5nm. hard to tell what's going on with the stick just looking at the exterior in those vids.

NATOPS does discuss forward stick movement in order to stay in the 10deg pitch realm during flyaway

In many videos showing the Tomcat taking off from a carrier I noticed that during the 2 - 3 second launch the pilot is gradually pulling the stick so that the elevators are pretty much fully deflected the moment when wheels leave the deck. If we do it in DCS we end up pretty much stalling the aircraft and usually with a 60+ degree nose up. Is this realistic?

I also wonder the same.

IRL are you supposed to hold the stick aft before launch & then to neutral/slightly up, just after passing the Cat stop?

If I understood Victory correctly.

The acceleration from the catapult will put the stick full back if it's not held (as seen in the photos). As soon as you are free of the cat the stick will jump forward (as the acceleration stops) and will return to near neutral position.

In DCS we have none of these forces, so if trimmed for takeoff, just leave the stick neutral, it will be fine :)

I'm actually finding myself needing to slightly push fwd most of the time. Keeping the nose at around the +8 Deg

I find she wants to naturally pitch up as soon as she leaves the deck. I don't alter trim levels, I just react to what she's doing with the stick which is usually a bit of stick forward and a shallow bank towards steerpoint 1. As soon as the flaps are up and the gear retracted, she settles right down.

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I find she wants to naturally pitch up as soon as she leaves the deck. I don't alter trim levels, I just react to what she's doing with the stick which is usually a bit of stick forward and a shallow bank towards steerpoint 1. As soon as the flaps are up and the gear retracted, she settles right down.

 

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You need to fix your trim. It’s supposed to be 2 degrees nose up according to the cat launch training mission (I believe that’s where I remember that information from, all the reading about the Turkey that I’ve done blends together). As modeled, when on the cat with full flaps, it goes to almost 10 degrees nose up, which is going to cause a massive headache when you come off the end of the rail.

It's really not an issue. Just the difference between FBW in the Hornet and a "stick and rudder" plane like the Tomcat. You have to fly her off the deck rather than a computer doing it for you.

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I might tone pitch up moment down a little bit at low speeds (i.e. right after takeoff at high power settings), will do some testing soon. Are you full flaps on the cat launch?

I might tone pitch up moment down a little bit at low speeds (i.e. right after takeoff at high power settings), will do some testing soon. Are you full flaps on the cat launch?

Yes Sir!

Damn, I want to believe what you're saying but none of that forward stick pushing is ever seen in the videos:

 

 

They just pull (or inertia does its work), roll off the deck and centre with a nice 30-degree climb occurring next.

The video you linked shows exactly what Victory is talking about. As each aircraft approaches the end of the deck (also the end of the cat acceleration) the elevators are at full deflection. Then as soon as aircraft leaves the deck/cat and is no longer under the acceleration of the cat the elevators immediately return to their trimmed T/O position near neutral (as compared to the full deflection they were at). So if you're holding full aft stick to simulate what you're seeing in the video, you need to release that aft stick pressure as you come off the deck to also simulate what you're seeing. If you continue to hold the aft stick pressure after coming off the cat then you're deflecting your elevators more than what's in the video and of course you'll stall out.

I'm asking why is such stabiliser position causing me to go nearly vertical in DCS when none of this happens in the videos?

In the videos, the horizontal stabs are in the normal position as soon as the aircraft rotates. You might just need to look closer.

More importantly, they are aerodynamically driven back to the normal position the instant CAT acceleration stops.

The Aerodynamic force instead of driving the nose up, drives the Stablators (Stabilatorons?) back down. It's not something you can simulate by holding your joystick back since holding the stick back implies to the game you are applying some impossibly high force on the stick preventing it from falling back forward as aerodynamics take back over as the main force on the controls.

And then there's the whole Bobweight issue which as you dip off the deck would actually forward load the control stick for a second, and the eddy current damper that tries to smooth that out (and is also why the stick doesn't immediately slam all the way backward as the cat fires because that would be hell on the bump stops.)

Basically you should only expect so much from the sim given your interface hardware.

The Aerodynamic force instead of driving the nose up, drives the Stablators (Stabilatorons?) back down.

Aerodynamic forces don't drive any flight control surfaces on a hydraulically controlled aircraft like the F-14. Thats the whole point of having hydraulics. If the horizontal stabs are being straightened out by airflow you have a serious issue with your flight controls.

Damn, I want to believe what you're saying but none of that forward stick pushing is ever seen in the videos:

 

 

They just pull (or inertia does its work), roll off the deck and centre with a nice 30-degree climb occurring next.

You didn't understand what Victory said and you didn't watch your own video carefully. The Tomcats do exactly what Victory said both in the video and in game. The current setup in game is fine even if we don't get the aft stick movement due to the bob weights.

An additional factor is that when kneeled, the nose strut releases stored energy at the end of the cat stroke to help rotate the nose.

For the sim, there is no reason to hold the stick full aft, just go off at takeoff trim and gently pitch the nose up. Don't overcomplicate a simple maneuver.

The pitch was natural and easy to control, but that assumes proper trim and CG loading. The guys who came from Phantoms loved it in comparison.

proper trim and CG loading

I would love to get some info on that. Is there any weight and balance table/handbook available somewhere?

You didn't understand what Victory said and you didn't watch your own video carefully. The Tomcats do exactly what Victory said both in the video and in game. The current setup in game is fine even if we don't get the aft stick movement due to the bob weights.

OK, I'll try to express my concern as simply as I can: HB Tomcat during the in-game cat launches requires no elevator movement to achieve the same pitch at rotation as the real-life F-14 with elevators fully up - why?

Yeah I must agree, I don’t think anyone has actually adressed what you’ve said and shown. IRL the evelators are at full pitch at the end of the stoke, whereas if you did that in DCS you would pitch up 60 degrees and stall. This has absolutely nothing to do with trim, I don’t get how people aren’t understanding that, as the elevators are at full deflection so pitch trim is redundant.

Aerodynamic forces don't drive any flight control surfaces on a hydraulically controlled aircraft like the F-14. Thats the whole point of having hydraulics. If the horizontal stabs are being straightened out by airflow you have a serious issue with your flight controls.

If you aren't applying any force on the stick it will be driven back to trimmed position once the Acceleration stops pulling the stick back. Once you take your hand off the grab bar/flimsy gauge cowl and put it back on the stick then the Hydraulic boost keeps the control surface where you tell it to go. Because remember it's Hydraulic Boost not Hydraulic driven like the spoilers. Think Power Steering, not excavator arm.

I would love to get some info on that. Is there any weight and balance table/handbook available somewhere?

NATOPS which we can't officially link here but it's just a Google away.