Pirouette Maneuver - Can you execute it anymore?!

[Raviar]

Hello Hornet pilots,
is there anyone have problem with Pirouette Maneuver ? seems after the last FM update it really changed, its not easy to do it anymore.
like to hear your opinion if anyone can do it with clean hornet.

 

Thanks

Edited October 15, 2021 by Raviar

[oldcrusty]

14 hours ago, Raviar said:

Hello Hornet pilots,
is there anyone have problem with Pirouette Maneuver ? seems after the last FM update it really changed, its not easy to do it anymore.
like to hear your opinion if anyone can do it with clean hornet.

 

Thanks

I don't think the pirouette logic is implemented yet. I tried it from a pitch up to get above 25 AOA and below 210 kts and it simply looked like a sluggish rudder turn. Same when started in horizontal. When you have some more speed on the jet, say around 300 kts, the 'loaded' turns are very crisp. I like the way it handles at this speed range but... that's not a pirouette.

Edit: The first attempt was entered within parameters and looked slow (split s would take the same amount of time to reverse), in the second maneuver I entered at around 300 kts and it sort of resembled a sloppy pirouette.

 

Edited October 13, 2021 by Gripes323

[oldcrusty]

I have to make a small clarification here. In the post above I stated that pirouette logic has not been implemented yet.  Perhaps it has been, in the past. I do remember performing a classic, air show pirouette a while back and the yaw was definitely more pronounced. Currently, it looks like there is more roll. Even if the maneuver is done the way Wags demonstrated in his vid (done in an older OB build).

Someone commented on YT that I entered the maneuver incorrectly. Yep, not exactly the way it's done at an airshow but I did enter below 210 knots and above 25 deg. AOA so the pirouette logic should have kicked in. Although, starting this with nose up would not produce a snappy response. Then again, I'm simply relying on vids and some feed back as a reference... I've never flown the real bug.

[Raviar]

when Wagner upload his video I could do it pretty easily sometimes used it in Dogfight too, however the hornet flight model changed A LOT, and I cant do it anymore (randomly happen)! I dont believe entering to the maneuver is the issue, low speed about 90 to 110 knots should be suitable to start the maneuver by pushing the Rudder in the same direction of the turn and Stick to corner and same direction of the turn.

I dont care the maneuver that much, however its a noticeable changes on FM

Edited October 15, 2021 by Raviar

[Figaro9]

Yes, I think there were changes, but it seem closer to rw now. Iˋd say the pirouette works in dcs, but we probably still lack of aoa capability although some improvements have been made.

The maneuver in airshows is described in the us tac demo manual, only for E model though. 

1. Start 800ft above ground, 350 kts
2. Full Ab, pull 5-6g into the vertical.
3. At 5000ft agl full aft stick and hold  35° aoa . 
   1. You do get 35° in dcs only below ~ 200 kts, I can not do a constant aoa loop over the top so far at 35° aoa. fm needs probably some tweak here?
4. Capture 175 kts at 35° aoa and  when 40-50° nose low, apply pirouette input. Pirouette works best (for the e model) at 175kts according above mentioned manual.
   1. I can hold approx 150 kts at 35° aoa in the trk
5. Hold 35° aoa 
6. Remove Inputs.

I have red that in the lot 20 they initiate the pirouette inputs at 40° aoa....

 

pirouette 10-21.trk

[Raviar]

The flight model changed and I cant do it anymore, followed the exact parameters but its just deep tight dive spiral, at the best situation with by overriding FCS its get a little bit better but not even close to Pirouette 

[oldcrusty]

7 hours ago, Raviar said:

The flight model changed and I cant do it anymore, followed the exact parameters but its just deep tight dive spiral, at the best situation with by overriding FCS its get a little bit better but not even close to Pirouette 

Overriding FCS? You probably mean paddle switch. Pressing it would probably deactivate the pirouette logic but hey... some other crazy stuff could come out as a result.

I would wait till FM update happens...

[SUBS17]

9 hours ago, Raviar said:

The flight model changed and I cant do it anymore, followed the exact parameters but its just deep tight dive spiral, at the best situation with by overriding FCS its get a little bit better but not even close to Pirouette 

That is not how it works with FBW.

[Figaro9]

Heres a demo program with pilot notes presented by the saf display team showing target altitudes, airspeeds, aoa and throttle settings for different maneuvers. 

https://de-de.facebook.com/swisshornetdisplayteam/

We sould be able to pull 45° Aoa at 160kts in the lot20 before we apply pirouette input. By pulling to an aoa of 60° the nose would rise ~30° above the horizon (while the flight path goes down 30°). 

For more impressive pirouettes we need more realistic  aoa capabilites. 

[wilbur81]

8 hours ago, Figaro9 said:

Heres a demo program with pilot notes presented by the saf display team showing target altitudes, airspeeds, aoa and throttle settings for different maneuvers. 

https://de-de.facebook.com/swisshornetdisplayteam/

We sould be able to pull 45° Aoa at 160kts in the lot20 before we apply pirouette input. By pulling to an aoa of 60° the nose would rise ~30° above the horizon (while the flight path goes down 30°). 

For more impressive pirouettes we need more realistic  aoa capabilites. 

Now THAT is an interesting document for sure.

[MARLAN_]

While I don't have figures to provide, the Hornet pilot I know has said the DCS FA18 is very much lacking AOA ability & G-Onset

Edited October 21, 2021 by MARLAN_

[wilbur81]

On 10/20/2021 at 11:22 PM, MARLAN_ said:

While I don't have figures to provide, the Hornet pilot I know has said the DCS FA18 is very much lacking AOA ability & G-Onset

 

Was he a C and/or Lot 20 driver? You might have him privately contact the Devs if he's willing... it might help us get the FM even closer. They've certainly got their own SME's that, apparently, are content with AoA/G-onset for now.

Edited October 23, 2021 by wilbur81

[Figaro9]

Afaik ed is aware that aoa needs tweaks.

Here is a thesis on f-18 spin demo procedures. According to that document the pirouette works best at aoa ~45° and ~ 150kts. We do not get there atm in dcs.

There are graphs showing yaw, roll and pitch rates as well as aoa. Aoa goes up to more than 60°. And yaw rates are up to 50° if thrust is split  (max/idle).

Yaw rate is higher too in dcs if you do so, but if you try max/idle, you enter a unrecoverable flat spin and the arrows show up almost immediately… With mil/idle split set I managed to do a full 360° pirouette in slightly more than 9 seconds, which means an average turn rate of almost 40°/s. Without split-throttles it is approx 3 seconds more.

There is some data available to improve aoa capability (and pirouette logic) in dcs. 

 

https://trace.tennessee.edu/cgi/viewcontent.cgi?article=3738&context=utk_gradthes

[wilbur81]

On 10/24/2021 at 6:56 AM, Figaro9 said:

Afaik ed is aware that aoa needs tweaks.

Here is a thesis on f-18 spin demo procedures. According to that document the pirouette works best at aoa ~45° and ~ 150kts. We do not get there atm in dcs.

There are graphs showing yaw, roll and pitch rates as well as aoa. Aoa goes up to more than 60°. And yaw rates are up to 50° if thrust is split  (max/idle).

Yaw rate is higher too in dcs if you do so, but if you try max/idle, you enter a unrecoverable flat spin and the arrows show up almost immediately… With mil/idle split set I managed to do a full 360° pirouette in slightly more than 9 seconds, which means an average turn rate of almost 40°/s. Without split-throttles it is approx 3 seconds more.

There is some data available to improve aoa capability (and pirouette logic) in dcs. 

 

https://trace.tennessee.edu/cgi/viewcontent.cgi?article=3738&context=utk_gradthes

Interesting. Since the 2018 release of our Hornet, I've always been puzzled with the (apparent) lack of rudder authority in certain low-speed regimes. It may be perfectly accurate for the FBW FCS, but I have wondered if the Hornet should have more rudder/yaw authority than it currently does in DCS.

By the way, what an amazing document find! 

Edited November 7, 2021 by wilbur81