Forcing a dive?

I am currently working on a project that involves a flaperon plane (wing) falling from a large height.
Is it currently possible to make the craft forcefully make a dive straight down till an altitude and then pull out. I am trying to achieve this whilst maintaining minimal effect the the rest of the operation during auto mode,
Many Thanks

Why? That is going to cause lots of stress.

Assuming it can handle it’s terminal velocity /if you have flaps/airbrakes that can handle it .
There is no mode/command to do that, but it could be programmed as another mode, or by a companion computer.

Programmed as another mode? Would I just put it in manual and let gravity & physics do the rest of the work? And could this easily be done as a mission? Ie. Fall straight down until altitude then proceed, such as doing some automated landing?

It’s part of a project in currently working on

A properly balanced/built plane would not maintain nose-down attitude by itself.
Of course, you could pit it in manual and do the dive, when you asked:
"Is it currently possible to make the craft forcefully make a dive straight down till"
I thought you meant to make the AP do that maneuver.
of course you can do it manually. (only limited by the physics/ mechanical configuration)

Allow me to tell you some backstory
The project will involve launching the craft from an airborne point, (a high altitude balloon ). In an ideal world I would write a mission that will cause it to point straight down (or 88deg to allow guidence) then at a predetermined altitude, it will pull out of the dive at a predefined rate (as to avoid wing folding) and land at a specified point. I would prefer to have it completely autonomous. Is this possible to do or what is the closest alternative. I will have mavlink connection throughout. I hope this clears confusion

Yes, basically what I guessed.
In that case, my first reply is correct. To get down as quickly as possible, you need to program a mode for that, or use a companion computer to control it.
Normal parameters that define the flight envelope are not made for cases like this.
Another , maybe simpler solution, may be for he flight computer not to control the plane using virual sticks, but to reconfigure the planes parameters to allow such attitude, and demand very high airspeed. But that alone will not result in as much as 80% dive.

So that would involve source modification? And what do you mean about using a companion computer? I apologise if I am being a pain

if your dropping from almost directly above your landing site you could set min pitch and decent speed to really high numbers like -80 @ 50m/s and it should go into a near vertical dive down to your RTL altitude.

If it’s dropping from a balloon, it will likely move off downwind and not be directly over the launch point. The dive might then leave you at a lower altitude than you need to get back to launch as of course you will be facing a headwind on the return journey.

Plenty of people do this. Hang out on and you will occasionally see some aircraft/gliders.

You can simulate this sort of thing all day long!

You can have multiple landing points in Arduplane and it will RTL to the closest.

Rushing to the ground will decrease your options at the bottom of the hill.

These are worth a watch

best method will probably involve a code hack but I would suggest limiting elevon throws as a function of (density) altitude because your stall angle of attack will drop dramatically at high altitudes anyway due to Reynolds number effects and you want to keep the wing flying well within its flight envelope. Doing this will also have the effect of limiting the pitch angle as you desire but you’ll probably find that it will begin to “fly” much higher than you expect.

You’ll also have to factor the controller gains with density altitude too

It would be like dropping a piece of paper or sheet, it will try and fly, all the time moving downwind. Rather get back to the launch site and spiral down. This chap was everyone’s hero back in 2003

Ever look here?
Not sure if they ever got permission to do in USA due to FAA.

Very sadly the lead for that, Lester Haines passed away.

Here’s my theoretical approach from a long time ago when HITL was all the rage and APM1’s were fashionable.

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Kids of today, don’t know they are born, mutter mutter

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Hi , i want to do dive with fixed wing uav , using cube pixhawk any solution ?