Free Flight, Free Speech

bomber wrote:Start from 10k then try...

You're stalling and going into incipient spin.... allow the plane to go into a developed spin.



You'll know the difference.

Simon

Yup. all difference in the world

I wanted in the first vid to reach 5000 to spin it, but it just takes so long to go up there, and I decided to stall-spin-recovery it at 3000.

This time I cheated my way around to 10000, instead, so I could proceed right away. Engines on. Up the cheat way to 10000, mixture down, recover engines and your plane, as we saw above recovered himself close to 9800. So I was ready.


Then, I went stall-spin- and let it sping like 10 turns. then apply rudder, and the recover came up just as the manual says~~~~~

That was glorious!


I did it to the right, so I climb back like at 6000, went for a left spin. It also worked. I got a black-out so after applying rudder moved to outside view (thinking--- did I hit ground?!)
Not at all, got the external view of the proper spin recovery and it was very very impressive bomber.

The runway was just right there to go for some cross wind landing too

Quite a ride!

Stall Spin Recovery maneuver Bomber's Pup

sanhozay wrote: Are you pressing Ctrl-U repeatedly to get up to 10000ft? That might be triggering the crash detection because the altitude changes so quickly? If you want to try the glide test, use Location - Position Aircraft in Air. It should glide, although it may not do so in a straight line.

Yup.
But I tell you, unless an invisible UFO I crashed nothing in my way up.

Also, the plane reaches whatever altitude I need/want without crashing. It dies way after it starts descending as a cork-screw.
That is, IMHO, what trigger that crash detection system.

Anyway? what's the meaning of that there? did I lost my wings? Did I hit a bird?
That's quite inappropriate to loose an aircraft just out of Gs, unless you are simulating the wings leaving the fuselage.

(which would be better simulated by a strong torque spin to ground... again, IMHO)

@G-SHOZ

I did location to go to 10000,
As soon as the thing start spinning, the wings say, "good-bye sweetheart"

And its game over.
Game over

I find both other fdm's go into a spiral dive...

I agree use location aircraft on the air.... however I wonder if different front ends produce different effects..

I'll see if I can video, however it crashed to d t last time..

Israel.... please calm down, I understand your opinions yet feel a bit embarrassed as this has been my most pleasurable experience of working with the FG community.....

Richard..... don't let it get to ya. You've stated your reasons and I personally can live with them.

IAHM-COL wrote:its game over.

Indeed.

You didn't specify a forward velocity and it would appear that, somewhere between Aeromatic++ and JSBSim, the model become mathematically unstable. This is not entirely surprising, given that an aircraft at altitude with no forward velocity is not a normal flight condition. I suspect some division by very small numbers somewhere that make the forces and moments go haywire.

When I conduct a glide test it doesn't respond as well as some other aircraft, but it does glide and it took a lot of repeated tests adjusting the AeroRP and CoG to get it to do so. Even with CG on the longitudinal axis, it tends to roll to one side, something I don't yet know how to correct. If Richard's FDM does the same as my Aeromatic FDM and Bomber's composite FDM doesn't, there is an opportunity to learn something.

But I tell you, unless an invisible UFO I crashed nothing in my way up.

By Newton's second law, force = mass x acceleration. Creating an extreme acceleration by pumping Ctrl-U develops an excessive force on the model which my model is detecting and reporting as a crash. Such massive accelerations are not experienced in normal flight unless an aircraft crashes -- the rule exists in the crash detection system to detect a crash into a solid structure.

I hate the crash detection but I put it in to avoid mathematical instability after structure contacts hit the ground (the aircraft would ping 1000ft into the air when striking a wing). Again, something else I don't yet know how to fix.

Look at mine for the structure

bomber wrote:Look at mine for the structure

I have similar structure contacts but I'll double check the positions and try using your numbers. Is it likely to be the damping that makes it go wrong? To be honest, I don't know if it still has the pinging behaviour. I think I read somewhere at the time that it was bogey contacts intersecting the ground at weird angles but I've seen it ping off the top of the fin.

I do drop tests from like 10ft and others.... I got the wing tip numbers from watching and adjusting as the wings on the glider struck the ground when spawning.

I did some thinking about spin last night..

2 types of spin...

1) Yaw spin
2) Roll spin

A Yaw spin will not give you a black out, and you should be seeing some sky from the cockpit, your airspeed will be 39kts, downward velocity will be -101fps with your AoA seen by the fuselage being about 41degs. So Israel your first spin was a yaw spin.

A Roll spin will give you a black out, and more than likely you'll be pointing directly at the ground, your downward velocity will be high and the AoA low. So Israel your second spin was a roll spin.

Regards

Simon

@bomber , @G-SHOZ

HI Guys
So I was testing ways to get Sanhozay's Pup gliding test to at least occur.
This is the thing.

1. CTRL + U: Wing crash
2. Spawn in RWY, Location 1000 ft: Wing Crash
So, G-SHOZ suggested the velocity at the moment the craft changed location to 10000 was important, so I tried
3. Spawn in RWY, take off, reach stable speed at 65 KTS, straight flight, then Location to 1000: Wing crash [I noticed when the plane relocated to 10000 ft it did so with 0 KTS, in spite before the relocation it was flying at 65KTS)

So, last option I could consider was using the launching to get me there
I added (--altitude=10000 -voc=65) to my launching parameters

That gave me the opportunity to compare craft's behaviors

Here is my experimental outcomes

Bomber's Pup [Video] Glide test 10000 ft/initial 65KT

Sanhozay's Pup [Video] Glide test 10000 ft/initial 65KT