Beagle Pup Development [crossposted]

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IAHM-COL
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Re: Beagle Pup Development [crossposted]

Postby IAHM-COL » Tue Nov 15, 2016 4:05 pm

so you are saying that the moonroof is caused by something bomber added in T4T-pup100-set.xml?
https://raw.githubusercontent.com/IAHM-COL/gpg-pubkey/master/pubkey.asc

R.M.S.
If we gave everybody in the World free software today, but we failed to teach them about the four freedoms, five years from now, would they still have it?

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Re: Beagle Pup Development [crossposted]

Postby IAHM-COL » Tue Nov 15, 2016 4:05 pm

also, I pushed v0.2.3 to FGMEMBERS now, for those interested in keeping updated Pup in the experiment (the other thread)
https://raw.githubusercontent.com/IAHM-COL/gpg-pubkey/master/pubkey.asc

R.M.S.
If we gave everybody in the World free software today, but we failed to teach them about the four freedoms, five years from now, would they still have it?

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Re: Beagle Pup Development [crossposted]

Postby bomber » Tue Nov 15, 2016 4:30 pm

"If anyone ever tells you anything about an aeroplane which is so bloody complicated you can't understand it, take it from me - it's all balls" - R J Mitchell

sanhozay
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Re: Beagle Pup Development [crossposted]

Postby sanhozay » Tue Nov 15, 2016 5:44 pm

It's just the view position defined in T4T-pup100-set.xml. If you look up, the camera ends up above the inner skin of the cockpit and because the inner and outer skins only have normals on the outside, you can see the sky through the inside of the outer shell.

If you change y-offset-m from 0.63 to 0.43, it goes away. It's nothing to worry about.

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Re: Beagle Pup Development [crossposted]

Postby sanhozay » Tue Nov 22, 2016 11:46 am

I've just committed v0.23.1, which fixes a bug with pointmass weights. If you are flying or testing using my pointmass weights and fuel & payload dialog, I'd suggest you delete the saved aircraft data in $FG_HOME/aircraft-data/pup*.xml after updating to this version, otherwise you might experience some weird CoG imbalances.

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Re: Beagle Pup Development [crossposted]

Postby sanhozay » Fri Nov 25, 2016 12:36 pm

I have just committed v.026.0, which includes a major rework of my FDM.

It's regenerated using Aeromatic++ 3.3.8, with the propellers modelled using JavaProp, CoG and AeroRP tweaked, and drag and engine parameters adjusted to the performance figures quoted here: https://www.flightglobal.com/FlightPDFA ... 200659.PDF.

Resources directory has my Aeromatic++ parameters and JavaProp files.

It's not the finished article by any means, but the performance is coming out as good as I could have hoped for and it flies much better than it did a couple of weeks ago.

Code: Select all

Static full throttle RPM: 2350.

Altitude   RPM      Fuel Flow     KTAS
2000      2500      6.4 (6.5)  96 (95)
4000      2300      5.2 (5.0)  82 (82)
6000      2500      5.9 (5.9)  94 (93)

Max speed (~sea level, full rich, redline RPM) 110KTAS (110).

Table shows measured values, quoted performance in parentheses.

In all cases, full fuel, 170lb pilot (which I suspect should actually be up to MTOW), mixture leaned to 50*F rich (which is where the asterisk is on the EGT gauge), standard atmosphere (00000KT, 15*C, 29.92).

@Bomber: thanks for your help with this.

EDIT: I should add that it doesn't play nicely with winds above 12kt at the moment and will get blown over.

@IAHM-COL: You'll probably need to set the roll trim back to zero on the autopilot and elev trim to 2.80.

bomber
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Re: Beagle Pup Development [crossposted]

Postby bomber » Fri Nov 25, 2016 2:17 pm

Sanhozzay... thanks very much, this IS the fun part of what we do.. :)

I think IIRC the RAF has a tolerance of 10% on this kind of testing.. and your maximum is only 3%

If I was to ask you a favour it'd be to remove your autopilot (as I'm having trouble getting it back to basic) and then add it back but using a single point of call up, if that makes sense.

If you didn't know I've just re-done my cessna 172a and can use the standard autopilot (out of the box) on it and so perform those alt tests... I can't do this on the Beagle Pup at present.

The stock autopilot also allows one to do rate of climb testing, which is a help.

regards

Simon

p.s. I'll re-zip my beagle pup for an update later this evening...
"If anyone ever tells you anything about an aeroplane which is so bloody complicated you can't understand it, take it from me - it's all balls" - R J Mitchell

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Re: Beagle Pup Development [crossposted]

Postby IAHM-COL » Fri Nov 25, 2016 2:58 pm

bomber wrote:
p.s. I'll re-zip my beagle pup for an update later this evening...


Hi Bomber

Will this still be valid after the zip you'll send me?
https://github.com/FGMEMBERS-NONGPL/Bea ... ll/1/files

You never told me whether merge or not; on the contrary you mentioned changes you wanted to apply.

Notice this pull request includes G-SHOZ recommended max steering value of 12.5 which I found to improve ground behavior (taxiability) quite by a large factor of 6 :D
https://raw.githubusercontent.com/IAHM-COL/gpg-pubkey/master/pubkey.asc

R.M.S.
If we gave everybody in the World free software today, but we failed to teach them about the four freedoms, five years from now, would they still have it?

sanhozay
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Re: Beagle Pup Development [crossposted]

Postby sanhozay » Fri Nov 25, 2016 3:04 pm

I'm pleased with the progress. Stalls are lethal and it blows over on the ground in a moderate crosswind but it flies reasonably for the time being. I've been focussing on prop/engine performance and drag really.

What I find remarkable is that, with the JavaProp-modelled Sensenich prop and the exact same tuning in the Lycoming engine (bsfc, volumetric efficiency, ram air and air intake impedance), the Pup 150 is also very close to the numbers. The Pup 160 is anybody's guess because they only made 9 before the government pulled the plug on Beagle.

If I was to ask you a favour it'd be to remove your autopilot (as I'm having trouble getting it back to basic) and then add it back but using a single point of call up, if that makes sense.

Here's a version with the generic Flightgear autopilot and dialog. I made a git patch so I can easily make these for any subsequent version.

Beagle Pup 0.26.0 (Generic Autopilot)

bomber
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Re: Beagle Pup Development [crossposted]

Postby bomber » Fri Nov 25, 2016 3:11 pm

yeh yeh.... everything that's been discussed here has been implemented.... (hopefully).

I just want to re-check the flap lift stall speed, before zipping

Except the rotation interia issues KL has concerns over... I just can't find any solid scientific justification for adding additional inertia on a planes that's known as a 'sports' version. I simply don't have any extra weight to put on the wings. That said hopefully when I come to do bigger planes that clearly will have large roll inertia and if this doesn't present itself, action will then be justifiable and filter back down to lighter planes.

Sanhozzay ..... you star !
"If anyone ever tells you anything about an aeroplane which is so bloody complicated you can't understand it, take it from me - it's all balls" - R J Mitchell


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