Props tailor-made for a given plane
Hi Ivan,
It would really be cool to be able to tailor-make decent props for a given plane more easily!
The pictures of graphs in your posts are generated by your spread-sheet, I suppose... It also helps to visualize whatīs going on.
The non-linear graph sounds logical, as it would save on points where it was more of a straight line so as to use them to smooth out more curved places.
Good night!
Aleatorylamp
Giant: Great performance results!
Hi Ivan,
Thanks to your guidance and proverbial pacience, after all this work of adjusting and tuning, and then re-adjusting again and again as new factors cropped up, I have finally managed to get the Giantīs .air file into a completely different state altogether. It is actually doing what it is supposed to do!
The last hurdle was re-adjusting Drag to adjust descent and approach so that landings could be viable. With that, the excessive RoC higher up also automatically corrected itself, although performance near and at the ceiling is quite poor unless tanks are half empty.
With this, the Giant is finished now! It has definitely been worth while, and the improvements have even been quite a bit greater than what I had initially expected. The only thing I havenīt been able to do after some improvements on the model itself, is to SCASM the virtual cockpit again, as the necessary programs to do so wonīt work on my computer.
However, the virtual cockpit back wall is adjusted so that it wonīt block the padlocked chase-view, and the fact that the virtual cockpit itself disappears is not altogether a disadvantage, because it allows the locked enemy to remain visible, otherwise hidden by the interior-view cockpit walls.
So! Now Iīll tune the other Giant with the darker textures, the triple fin and the more expensive Maybach engines to do what itīs supposed to do too, and Iīll be able to upload the planes shortly!
Cheers,
Aleatorylamp
Flight model satisfaction
Hi Ivan,
Itīs interesting that you know how to make useful programs - they come in handy! I can only program in QBASIC, and itīs a bit obsolete now... I havenīt learnt to use spread sheets either, so Iīm limited to manual entries in AirEd, but itīs not too bad at all with CFS1!
To compare 2 .air files I always open 2 windows with AirEd open side by side, and go down both listings in order, and it works OK.
After the FS98 limitations that I have been used to until now, it is indeed satisfying to experience the increased control that CFS1 offers over aircraft performance! The main problems I ran into towards the end were my own fault, as I should have noticed that the .air file had something "broken" in it and renewed it long before. Anyway, I have just adjusted the second Giantīs better engines for 8200 ft rated altitude, and Hp is fine all round... Iīm now adjusting RoC for different altitudes.
You mention fuel tanks: An interesting thing on the Giant was that it was fuel-trimmed. Prior to take-off, the angle of attack for the sustaining tailplane was set from outside, depending on the bombload to be carried, and then the plane was tanked up, always leaving the 2 foremost of the cylindrical inboard fuselage tanks empty. The Mercedes engined Giant had 8 tanks, and the Maybach one, 10. This way the plane was trimmed for take-off and climb. Then during flight, the fuel engineer could pump fuel into the two foremost tanks to change the CoG for level flight. He also kept the central tank under the top wing full to feed the engines.
A trimming-wheel was also available - it is visible on cockpit photos, but only used when the plane was empty and low on fuel, and there was nothing to pump into the forward tanks to lower the nose.
Anyway, in CFS thereīs no fuel menu, so one canīt move the fuel around from one tank to another and the trimming wheel has to be used. For CFS1 I have only defined 2 fuel tanks, left and right, each with half the total fuel.
Iīll wait a bit for your notes on the V-Cockpit then, before I upload the Mercedes Giant.
Cheers,
Aleatorylamp
Disassembler and SCASM works now
Hi Ivan,
Thanks a million for your help! My SCASMing setup finally seems to be working.
Iīm now going through the instructions you and Hubbabubba sent me, in order to join the .scx listings of the separate v-cockpit models to the .scx listings two v-cockpitless Giant models, so as to re-compile them afterwards.
OK, then
Cheers,
Aleatorylamp
SCASM fixed Virtual Cockpit!!
Hi Ivan,
I can hardly believe it!! I inserted the V-Cockpit code into the Giantīs source file and the newly SCASMed virtual cockpit works perfectly!
I also had a look into Hubbabubbaīs thread on AF99 colour codes in hexadecimal and with this info I was even able to find the individual cockpit parts in the source file and identify their vertices to eliminate some hairline cracks.
The next step now is to simply put the V-Cockpit code into the other Giantīs source code and simply change the dark green cockpit parts to dark blue, and presto!, the other Giant will have a perfectly working Virtual cockpit too!
Iīm just tweaking a few things in the .air file and will be uploading the planes soon!
Who would have thought that an old dog could learn a new trick?
Thanks a million!!
Cheers,
Aleatorylamp
2 Attachment(s)
Second Giant V-cockpit also SCASMed
Hi again!
The second Zeppelin Staaken R.VI, with the Maybach engines, now also has its SCASM-fixed V-Cockpit.
This one has a slightly darkened night-bomber splinter-lozenge livery in dark-blue-blue-orange-red-grey with a blue cabinroof and blue interior window frames, whereas the Mercedes-Engined Giant has a green forward-fuselage and window-frames, and an overall brighter conspicuous anti-friendly fire colour scheme in green-red-orange-blue-dark blue.
As soon as Iīve finished last minute adjustments on the .air file iīll upload them.
Cheers,
Aleatorylamp
Cool Looking Giant Aeroplane!
Glad it all worked out for you.
It does look cool from the screenshots.
I have also made some progress with the Propeller Tables.
Hopefully there will be something worth flight testing shortly.
The candidate for flight testing is a Ki-61-Id that has been waiting its turn in the paint booth for years.
- Ivan.
Volunteer for flight testing
Hi Ivan,
Tell me what youīre testing for and Iīll I volunteer for the task!
Cheers,
Aleatorylamp
Flight Testing a Propeller
Thanks for the offer Aleatorylamp.
I don't think this is a task that I can delegate though, especially not with the first try at Propeller Tables.
I suspect testing this time will be a bit different from my usual protocol.
My plan (very subject to change) is this for now:
Gather enough information for a data sheet on the Kawasaki Ki-61-Id.
I MIGHT already have this but can't tell right this moment because any data and references would be on the HDD for my dead laptop.
(It would also help if I could remember where the notebook is that contains all my old test record sheets.)
Run a full flight test on the Ki-61-Id (version 0.55) with the propeller as it currently stands.
Engine Power at various altitudes
Level Speed at various altitudes <-- This is the part that takes the longest
Climb Rates
Service Ceiling
Also note the Propeller Pitch, Thrust, etc under various conditions.
Tune the Propeller Tables via Spreadsheet.
Plug in the new Records 511, 512.
Re-Test.
There ARE a couple new developments though.
A replacement for my dead laptop was ordered last week and should arrive in a few days so I will have a place to load all the accumulated data from the old machine. Just need to figure out how to get license from the old MS Office and Anti-virus onto the new machine.
I also found my command line Spreadsheet to AIR File record conversion program. It actually was written back in September 2010 from the date of the source code file. Now I just need to go over the program and make sure it does what I am expecting.
Plenty of things to do.
- Ivan.
Concept question: Engine+Propeller+airframe=performance
Hi Ivan,
I have a concept question for you, as I canīt solve the balancing out of the parameters for the Maybach engined Giant, where Iīve been trying to adjust all the different parameters that affect power and speed.
Either RPM is OK and Hp 25 hp too low, or RPM and climbing are too high and Hp correct. I was also re-adjusting the Propeller Efficiency and Thrust tables.
On second thoughts now, I wonder if perhaps the propeller tables neednīt be touched, as these fit aircraft speeds rather than engine RPM or altitude. Perhaps, really only the Torque graph needs adjusting (with its dip 100 RPM before before full PRM), and the Friction Graph, after setting the compression and boost-gain parameters, of course.
The aircraft is basically the same as the Mercedes engined one, except for 500 lb more dead weight (the engines were heavier), and the engines very similar, but better.
Performancewise, the Maybach engined aircraft:
a) higher compression: 233.83:1 instead of 200.6:1
b) had a 1700 ft higher ceiling: 14,100 ft,
c) got its full 245 Hp at 8200 ft as opposed to the otherīs which was 267 Hp at 4300 ft., (boost gain was 1.4 instead of 1.22), meaning that when the Mercedes engine got to the Maybachīs rated height, it had already lost a lot of its 267 Hp, and the Maybach one was at peak performance.
d) was 3.5 mph faster at full speed level flight, with 84 mph TAS instead of 80.5
e) average RoC was 328 fpm, 33 fpm higher than the otherīs 295 fpm
f) Full RPM was 1400 instead of the otherīs 1450 RPM
So the question is essentially:
Can the 2 Propeller Tables in theory be left alone?
Thanks in advance for your answer. No hurry!
Cheers,
Aleatorylamp