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Staggerwing on floats...

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Folks ;-)Needing a break from bulldozing landscapes (!) and waiting for more feedback from testers, I did a floatplane version tonight!Haven't fully sorted the flight model yet (it still crashes and sinks..) but I'll get there - it IS my first floatie :-roll I gather now that there mustn't be ANY contact points that touch the water...And no, it isn't amphibious - but dont worry, I'll upload both types and paint sets are compatible (i.e. the paint sets carry BOTH wheel and float textures). The rudders don't turn (blame BSP.exe) but they do retract, jess' like the real ones ;-)Anyway, whilst you're admiring the tank-sized floats (they ARE to scale and weigh 600lbs each - no wonder they do bizarre things to the handling :-lol ), look at Agtim's lovely handiwork around the lake edges and surroundings. This new SRTM elevation is lovely!http://forums.avsim.net/user_files/160527.jpghttp://forums.avsim.net/user_files/160528.jpghttp://forums.avsim.net/user_files/160529.jpghttp://forums.avsim.net/user_files/160530.jpgSpeaking about paint sets, would anyone feel like doing one or 2? A BFU one would be nice, as would something with a "G" on the tail for UKS. I will forward hi-rez textures to anyone interested and I'll even do the resize and 8-bit palette for you if you'd just like to do the 24-bit textures. And yes, I'll even help out with callsigns too ;-) If you don't have my email, post here please!Regards,Jon Point

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Nice work, both versions looking great ! :-)1200 lbs of floats ?!?! Whew...best not top up the fuel and load the cabin full !I'd guess 600 lbs for the pair....

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Tom,Did I say 'each'? I did! Whoops.Naw, it's total. 600lbs is a lot for a tyke like the Staggerwing. That makes it 300lbs heavier than the wheeled version but the weight isn't the issue - it's the fact that it's suspended nearly 3ft BELOW the CofG. This shifts the CofG to somewhere around your feet (i.e. lower wing), instead of somewhere around your waist (i.e. between the wings). Slow, steep turns? Uh oh...They also knock off about 15MPH in top speed so far ;-):-waveRegards,Jon Point

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Yeah, I thought so :-lolOf course, there have been aircraft that floats helped fly faster as well..Indeed the handling sure can change with something like that. Many people don't note the difference between 'center of balance' and 'center of gravity'Anyway, nice job Jon.

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"Many people don't note the difference between 'center of balance' and 'center of gravity'":-lolI didn't mean to sound stupid there, just not choosing my words properly. The pontoons move the balance point forward, but this is somewhat compensated in flight ;-) Problem is at low speeds, in sharp turns (I know...), the Staggerwing can turn on a dime - IF you keep the speed above ~60kias. If you drop below 60kias in a steep turn, it slips real fast :-( I mentioned this before about how the high amount of lift suddenly disappears at 45 degrees bank!With the floats, it seriously resists banking at low speeds and just loses altitude instead :-eek I have some data on the float version but not much, apart from weights and max speeds etc (somewhat higher and somewhat lower respectively). I compared some other wheel vs. floatplane data and it showed similar issues - lower max and cruise speeds, higher stall speed under banking.I'll get it sorted, but I'm determined to and keep it honest ;-)PS the panels are almost done (back, side, extra and F2 forward). F3 forward is still unfinished and I deleted the quarter views. Bleedin' Bravo base needs 4 of each texture :-roll I'll put them in on V2.0 - if you can get me some more photos ;-)Regards,Jon Point

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>I didn't mean to sound stupid there, just not choosing my words properlyNot at all Jon.. I wanted to indicate that YOU knew the difference between them based on the performance facts you were talking about :-) Glad to see her floating on the water, good work..

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Nice to see Forest Falls in the background, and congrats on getting the plane floating! (I keep trying with the Cessna but it floats like a brick flies - gotta try landing on the runway). I lost the conversation about CoG vs CoB, but with the Beaver floatplane, there is a death spiral where you do hard turns past the stall point and it goes into a downward spiral that would put a Camel to shame. I made Forest Falls as a quiet little retreat for myself. Now see what happens? The idle rich have moved in with their pleasure yachts and fancy biplanes, and its now a rich man's playground. Well fine, see if I care. But just to remind you, the sign at the end of the wharf says No Fishing. Hah.By the way, its a tricky takeoff because the lake there is (in FU3) very shallow in strange places. I'd hate you to bend your new floats. I think I put sticks in the water to sort of indicate a safe path, don't know if they're still there or not. The new terrain may look better, but probably uses the same classification file.Robert.

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Rob,The trick with the Cessna is to use "pontoons" in the flight model :-lol"I think I put sticks in the water to sort of indicate a safe path, don't know if they're still there or not. The new terrain may look better, but probably uses the same classification file."It's funny you mention that. Before resetting heights, I could taxi all of the markers, and only get stuck near the lake edge. Most of the area near the jetty is fine!Ah, this new terrain is nice. BTW, it should be possible to 'flatten' anything, including lake bottoms. This is because, even though Andre's mod with the yellow classification is intended for airports, once saved, it just becomes another red (i.e. urban) class. Not sure if you can put urban classes underwater (should check at Old Adaminiby...) but I tried "flattening" some non-airport areas last night with some success. In fact, I've created a couple of small glider strips which I may toy with later - after I get some of the Cascades airports done. One of them slopes - by creating 2 adjacent yellow areas and importing them separately. Unfortunately, I can't get enough slope to takeoff with but hey :-waveRegards,Jon Point

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All,My issues with the floats affecting low-speed handling are fixed! I re-edited the pontoon models to reflect proper lift and flotation (instead of just rectangular boxes) by calculating the true volume, and editing the drag effects to reflect the airfoil effect of the pontoons.Even though they ARE 'boxes', the taper above the waterline effectively removes any 'lift' generated by the top of the pontoon (which would be negative and cause the pontoon to be forced downward by passing air).Due to the relatively 'liftworthy' nature of the boat-keel part (the bottom), it provides substantial lift, almost entirely cancelling-out the extra weight (and balance shift) caused by mounting 600lbs of floats, 4ft below the CofG. By cancelling this weight with lift from the pontoons, their effect (at any speed above stall) is removed, and the aircraft flies substantially like a gear-up form, albeit with more drag.The result? It turns on a dime at 65kts or above. http://forums.avsim.net/user_files/160698.jpgOther changes are:Wheeled version speedsCruise = 28.5" manifold/5kft/175ktsFull speed = 32" manifold/5kft/189ktsFloat version speedsCruise = 28.5" manifold/5kft/163ktsFull speed = 32" manifold/5kft/179ktsSo we see a bit more drag, but the aircraft behaviour is very similar. The stall speeds are only increased by a small amount; about 3-5kts - almost impossible to notice - as we don't deliberately fly that close to stalling, do we?). Still climbs happily at 1500fpm too!BTW, there ARE different contact points for floats - I found 'em! (from 'segtype.h'):// a contact point that has no effect in water (for use near pontoons)#define AEROTYPE_CONTACT_SOLIDONLYNow, how do I get FU3 to realise that this is a floatplane?? Does anyone know how? SOMETHING tells FU3 whether to enable seaplane airports or not in the "Quick Flight" > "Airport" menus. It's not in the flight model (that I could find) - it must be in 'planetype' or something. however, there is no specific planetype for the Renegade or Muskrat. HELP! I can only select hard runways - no fun for a floatplane :-rollRegards,Jon Point

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Jon there must be a flag inside the plane resources. I remember the ship models for fu3 (earnslw5.res,ptboat.res) they all where made on a renegade base and the old floatplane (Lk300.res) also. Ansgar made a working float version of the DC3 (DC3_XC47.res), but not on a floatplane base, so lake strips are not visible at this plane selection, because it's a dc3 model base but you can land on the lake with it.Terrain modification.first flatten the yellow area, it becomes red, later just paint the red pattern to green or blue.you can modify elevation by exporting parts of a tile to a md3 model ready for gmax for endless adjustments, see.http://www.agtim.ch/fu3/MD3.php3I am using this way for smooting sharp edges on airfield borders. IOW Bembridge was done that way (before the NASA SRTM time) :-wave agtim

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Andre,Thankyou for both of those pieces of info! I realise that one of the files inside the resfile holds the key, but which one? On my search through build files, I couldn't find anything obvious. I did find the contact point info for the floats though ;-) I would rebuild them both into a Renegade base - except the cockpit is "start again" :-( I'll do some more resfile comparisons and see what I can find.Ah ha! Paint it afterwards... That makes perfect sense - now! Yes, I had the thought of extending some rivers too - the thought of crashing through the trees and splashing into the creek adds that bit of terror to it all :-rollRegards,Jon Point

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Dear All,I re-jigged the build script and inserted it into the Renegade! We now have an aircraft that registers landings at seaplane strips, as well as allowing you to select any strip for takeoff (land-based strips not recommended for the SD17S :-lol ).A few issues:* I have to redo the cockpit(s). This will take a few days ;-)* The wheel-based model (D17S) will also allow one to select seaplane strips. Obviously this will result in disappointment... I COULD do separate scripts for Bravo and Renegade bases, but I still have to redo the cockpit. It's also easier to have one base model, as the file positions vary between the base aircraft (and I couldn't be bothered too :-roll )Oh! The proof, the proof... Here 'tis ;-)http://forums.avsim.net/user_files/160822.jpgRegards,Jon Point

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Well, it WAS :-rollThe Renegade has a problem. You cannot delete the throttle, mixture and prop levers without causing CTDs in the F3 view :-boom (@#%$^*&!?)You can't move them either. :-newburn Funny, you can delete the ones in the F2 view :-hmmmNow I'm trying the Muskrat 'coz at least it uses a simpler setup and I seem to be able to delete instruments at will without trashing anything. I think the older models are more CPD-friendly anyway. This means I have to do the cockpit all over again :-( I have so far deleted all of the unecessary instruments and changed the panels and everything's still working.I have also decided to simplify the panel, back to something like the late 30's. This really just means removing the radio stack and replacing it with a single comms unit - and a transponder for good measure. ILS? This IS 1937 after all! Besides, why do you need ILS to land on a lake in daylight? :-rollThe saga continues :-walksmileRegards,Jon Point

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