Le 23/09/2011 16:47, Curtis Olson a écrit : > Hi Geoff, > > I'm starting to run low on ideas here. I assume you don't have any > crazy/severe turbulence turned on or your plots would be all over the > place. Are you running out of fuel and your engines dying? If you > open the autopilot dialog (F11) you can see the target speed and if > you have the hud turned on you can see the actual speed in any view. > If you are circling with a target speed of 150 and your airspeed is > less than than and you are decending, then definitely check your > engine output. There is a fuel dialog box under the f-14b menu and > you might double check that to see if you have any fuel in your tanks. > > For what it's worth, I'm rock solid in circling and the only time I > have ever stalled out of the sky or really got out of kilter is when > I've had severe turbulence turned on. Moderate turbulence at all > levels is actually pretty interesting because despite getting thrown > all over the sky, I still hit the carrier deck pretty spot on every time. > > Curt. > Still no tests yet but just a though, In normal use (without the UAV script) I know that after TO (flaps down) you have to rise the flaps in before engaging the attitude autopilot mode. If you rise the flaps after engaging attitude autopilot mode, the a/c start to pitch up consistently. This has to be documented or fixed. I'll try to bring the maintainer to his workstation ASAP.
Alexis > > On Fri, Sep 23, 2011 at 9:35 AM, Geoff McLane wrote: > > Hi Curt, > > Ok, removed my joystick, and entered a '5', but > still crashed while just in 'circle' mode - no route > entered ;=(( > > As usual Atlas provides a good 'view' as to > what happened - added - > ATLAS="--atlas=socket,out,<IP>,5500,udp" > to output to Atlas running in a 2nd machine... > > See - > http://geoffair.org/tmp/uas-01.jpg > for a graph of the flight... > > The two blips in the graphs show the first stall, > but it recovers and begins to climb back, and the > 2nd the second stall, this time too low to recover, > so into the drink ;=(( CRASH! > > This is a view of the 'crazy' flight track > http://geoffair.org/tmp/uas-02.jpg > > Obviously the pig-tail loops are the 'stalls'... > remember with NO joystick attached and starting > with centered controls (NumPad 5)... > > And if you want to load this track into Atlas, or > further study speeds, etc, then this is the > Atlas track data :- > http://geoffair.org/tmp/uas-01.txt > > Then on the NEXT flight I tried :- > IO="--generic=file,out,10,uas-02.csv,playback" > > Then I added a header line, to help analyze > it in say an OpenOffice spreadsheet import - > see - > > http://geoffair.org/tmp/uas-02.csv > > On this 2nd flight, this crash took longer, since > it (randomly) turned left first, where as mentioned > it holds more stable, but then eventually went into a > right turn, stalled, recovered, stalled again, and > CRASHED... > > And as you know well, downloading this file, and > using say - > > $ ./fgfs --fg-root=/point/to/fgfs/data --timeofday=noon \ > --aircraft=f-14b-uas --carrier=Vinson \ > --generic=file,in,10,uas-02.csv,playback --fdm=external > > you too can enjoy this fateful flight ;=)) > > In 'chase' view, you can clearly see the right roll > increase, the nose coming up, and the stall, recovery, > then repeated, and BANG, into the water... > > I know it is difficult to work on, debug, fix > something that obviously does not happen in your > case... > > Maybe if you do not enter any route, or something... > > And this is all with SG/FG git of 2011-09-14... > > Any other ideas? > > Regards, > Geoff. > > > On Thu, 2011-09-22 at 14:00 -0500, Curtis Olson wrote: > > On Thu, Sep 22, 2011 at 1:25 PM, Geoff McLane wrote: > > Hi Curt, > > > > A pleasure, and FUN ;=)) > > > > Yes, I know a low frame rate can play havoc when > > you are trying to fine control an aircraft from > > its attitude feedback, and I should have mentioned my > > rate, but is always in the high 50-70 fps range in this > > Ubuntu machine... so should NOT be a factor... > > > > > > Ok, 50-70 should be perfect. > > > > I just did another few runs, and this time it crashed > > just while circling... it was in a right bank, which > > got too much and the nose came up, and it stalled... > > I am mostly in the 'chase' view... > > > > > > This is really strange. I have seen nothing like this except when I > > inadvertantly applied external control inputs through a strange > > combination of linux virtual desktops and flightgear capturing the > > hotkey to come back to the FlightGear virtual desktop. > > > > > > So two thoughts here. If you have a joystick connected, could > you try > > unplugging it to see if that helps? Could you also press "5" on the > > numeric keypad to make sure all the flight control inputs are > > centered. Because of the way the F-14b FCS is wired together in > > combination with the yasim flight surfaces, you can still input > > elevator and aileron and trim and cause conflicts that you might not > > see in other simpler aircraft that use aileron and elevator > directly. > > > > > > The first time this happened at 2000 feet, it caught > > itself - leveled a bit and bumped the throttles, and > > began climbing back... > > > > But a little later, 20-30 secs, it happened again, and > > this time was still too low to recover, and SPLASH... > > > > I had not previously let it fly in the 'circle' mode > > for too long, but now note if I leave it in circling > > mode, it will eventually end up in the water... seldom > > lasts more than 5 or 10 minutes... > > > > You seem to be deliberately holding its speed down > > around 150 - I see air-brakes come up when greater > > than this, and throttle back - and although flaps (I think > > full flap?) are still applied, 150 must be quite 'low' > > for this sleek bird... > > > > > > Normal landing approach in the real aircraft I believe is about 120 > > kts? I fly 135 kt approaches in the simulator. It should be > able to > > hold 150 kts with the flaps down pretty easily. The point of > slowing > > way down when circling is to keep the circle radius small enough so > > you can see what you are looking at. If you fly the circle at 600 > > kts, your radius will be 20 miles (just guessing) :-) and you > won't be > > able to see anything. > > > > And I am not sure how many degrees each marking on > > the hud bottom bank indicator represents, and while it > > starts the banking in between the 1 and 2 of the 'big' > marks, > > at the stall point it is beyond the 2nd big mark, > approaching, > > even reaching the 3rd big mark, which is on the > > horizontal - ie 90 degrees! > > > > At the moment of stall it loses 1200-1400 feet in 1-3 > > seconds... while it can happen in a right or left turn, > > it does seem to happen quicker in a right turn... > > > > I now understand the 'reset' is a full sim reset, > > but that is not too helpful if you have set up say a > > particular weather, wind or something that you want to > > repeat... must get around to feeding that in, in > > the command, so a reset puts it back (I hope)... > > > > > > Well complain to the developers if a "reset" resets too > > agressively. :-) > > > > If you could describe a bit more where some of this > > is decided/calculated I too could try tweaking some > > values... > > > > I would probably bump the speed a little, and really > > watch the bank angle... those stubby little wings do > > not give much lift anyway, but the slender body gives > > close to none ;=)) > > > > As mentioned, I too have more than a passing interest > > in automated flight control... > > > > Regards, > > Geoff. > > > > PS: OT: I too searched a little for the expression to be > > a 'bunny', but could not really find anything ;=(( > > > > I am sure it comes from my Australian origin, and > > has the meaning to take the rap, take the medicine, > > sort of to be the guinea pig... > > > > > > Ok, I can understand that. Here we test cosmetics on little bunnies > > (so I'm told) but I'm sure we have to shave all their hair off > first. > > > > Why poor little bunny rabbits feature I just do > > not know ;=)) > > > > Maybe from when Australia had a big war on > > rabbits _MANY_ years ago, and put out millions > > of traps for the bunnies, as well as other methods, > > like poisons - myxomatosis... > > > > So to be a bunny was to be trapped ;=(()) > > > > Maybe other Australian's have a better memory than me, > > and can explain it better, but meantime I will blame > > my parents, or the Australian educational system, for > > giving me such a stupid expression ;=() > > > > On reading up on 'to be a Guinea Pig', another > > very confusing expression - not really a 'pig' and not > > from Guinea! - I found a reference that in Johnston's > > Natural History, they go by the name Spanish Coney. And > > 'coney' was the old name for a rabbit, a bunny... Huh! > > > > > > In Peru Guinea Pig is a delicacy ... cui ... never had it myself > that > > I'm aware of. > > > > Maybe the early immigrants to Australia decided to mix > > it up even more! ;=)) Or got it confused on the long > > boat ride half way around the world... > > > > > > Well just to summarize, if your frame rates are solid in the 30-60+ > > range, then the next thing I'm wondering about is a joystick or > other > > means of extraneous control inputs that could be confusing the F-14b > > AFCS. > > > > > > Thanks, > > > > > > Curt. > > -- > > Curtis Olson: > > http://www.atiak.com - http://aem.umn.edu/~uav/ > <http://aem.umn.edu/%7Euav/> > > http://www.flightgear.org - http://gallinazo.flightgear.org > > > > > > > ------------------------------------------------------------------------------ > All of the data generated in your IT infrastructure is seriously > valuable. > Why? It contains a definitive record of application performance, > security > threats, fraudulent activity, and more. Splunk takes this data and > makes > sense of it. IT sense. And common sense. > http://p.sf.net/sfu/splunk-d2dcopy2 > _______________________________________________ > Flightgear-devel mailing list > Flightgear-devel@lists.sourceforge.net > <mailto:Flightgear-devel@lists.sourceforge.net> > https://lists.sourceforge.net/lists/listinfo/flightgear-devel > > > > > -- > Curtis Olson: > http://www.atiak.com - http://aem.umn.edu/~uav/ > <http://aem.umn.edu/%7Euav/> > http://www.flightgear.org - http://gallinazo.flightgear.org > > > ------------------------------------------------------------------------------ > All of the data generated in your IT infrastructure is seriously valuable. > Why? It contains a definitive record of application performance, security > threats, fraudulent activity, and more. Splunk takes this data and makes > sense of it. IT sense. And common sense. > http://p.sf.net/sfu/splunk-d2dcopy2 > > > _______________________________________________ > Flightgear-devel mailing list > Flightgear-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/flightgear-devel ------------------------------------------------------------------------------ All of the data generated in your IT infrastructure is seriously valuable. Why? It contains a definitive record of application performance, security threats, fraudulent activity, and more. Splunk takes this data and makes sense of it. IT sense. And common sense. http://p.sf.net/sfu/splunk-d2dcopy2 _______________________________________________ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
