Speed & Temp Issues

[KalahariRover 0]

I know Kurt, but I go as far as I can, I can't reprogram FSX! :)Ok guys, I have a solution to my latest problem. Unfortunately there isn't a single value to be changed, we have to use the airfile editor. Line 1548, the very last one, atmospheric density on shaft torque (why the things I need are always at the bottom? :) ). It's a graph, X Y simple one. You'll see the X axis is locked, leave it locked. Work on the Y. I'll make a sort of table below with the X value and the corresponding Y value to be changed.X= 0.00204 / 0.00175 / 0.00149 / 0.00126 / 0.00114 / 0.00089Y= 0.99 / / / / 0.94 / / / / 0.81 / / / / 0.74 / / / / 0.69 / / / / 0.61I checked until 20000 feet. Believe me, you won't go higher with this plane, but it should work higher too. Things I said earlier are still valid: when you see you are at full throttle, don't decrese the RPM unless you are looking for a slower cruise with lower settings of both torque and RPM. I can't reproduce the increase in torque due to the reduction of RPM...This should be ok. I'll wait for your resultsCheers

Thanks a bunch for doing this. I really appreciate everyone's hard work here.

[spotlope 0]

I'd like to thank everyone for the work they've done, too. I just came off a flight with the new FDE and aircraft.cfg settings, and it's a thing of beauty. Nothing can match a gorgeous Carenado model when paired with an air file done by hardcore pros. Nice job, all of you! :(

[fritzreinhart 0]

Yes, a huge thank you to all of you guys. So happy that someone knows how to do FDE's, Caranado doesn't seem capable. Thanks again!Cheers,Fritz

[ricky76 46]

Yes, a huge thank you to all of you guys. So happy that someone knows how to do FDE's, Caranado doesn't seem capable. Thanks again!Cheers,Fritz

Perhaps, A better way of looking at it is, these folks have assisted in making an existing model, one that will be enjoyed even more by all! :( Too many people are giving Carenado a bad name. A dinner at a decent restraunt for two can easily be over a hundred bucks. So 35 bucks and a couple of "optional" and free (thanks guys) patches down the road sounds like a hell of a bargan to me for something that will be with me untill I tell it to go away! :Hug:Quote from Bill!I'd like to thank everyone for the work they've done, too. I just came off a flight with the new FDE and aircraft.cfg settings, and it's a thing of beauty. Nothing can match a gorgeous Carenado model when paired with an air file done by hardcore pros. Nice job, all of you! Nuff said! :(

[kiwikat 506]

Well I think seeing this fixed is gonna push me over... Time to get out the plastic!I wonder if it is easy to paint...

[Fede 0]

That's good news guys! You know, it took me so long I didn't even have the time to make a complete flight yesterday night, soooo tired...! But the important thing is the end result, now we can all enjoy this beauty, can't we?For the prop governor, I think I may have the tweak for it, but I'm not sure whether to implement it or not. I mean, you takeoff at full power, ok? Then you reduce the power and throttle, but climb settings are 1865 tq and 1900 RPM. So this would mean that if 1900 was the maximum rating you should climb with the prop full fine (and cruise as well), and as far as I know it's never like that. It sounds like a torture for the engine! :) Maybe this plane is different and it is supposed to be this way, but I'd rather leave it the way it is right now.Maybe Glen, you can ask your friend when you meet him about this, and let him tell you how the real one flies. There are some "secrets and tweaks" only a pilot flying it knows.. ;)Guys, I thank you for your time, reports and checking. Hopefully now I can make a flight! :)CheersFede

[Jigsaw 8]

I'd like to thank you as well of the effort you put into correcting the flight model and performance. Great job!

[Guest BeaverDriver]

That's good news guys! You know, it took me so long I didn't even have the time to make a complete flight yesterday night, soooo tired...! But the important thing is the end result, now we can all enjoy this beauty, can't we?For the prop governor, I think I may have the tweak for it, but I'm not sure whether to implement it or not. I mean, you takeoff at full power, ok? Then you reduce the power and throttle, but climb settings are 1865 tq and 1900 RPM. So this would mean that if 1900 was the maximum rating you should climb with the prop full fine (and cruise as well), and as far as I know it's never like that. It sounds like a torture for the engine! :) Maybe this plane is different and it is supposed to be this way, but I'd rather leave it the way it is right now.Maybe Glen, you can ask your friend when you meet him about this, and let him tell you how the real one flies. There are some "secrets and tweaks" only a pilot flying it knows.. ;)Guys, I thank you for your time, reports and checking. Hopefully now I can make a flight! :)CheersFede

Sure thing. As soon as I run into one I'll do that, OR I'll watch that video I've got coming closely. It is supposed to give a detailed view of the instruments through various phases of flight, so we'll see there too. What I do for takeoff is as soon as I have full thrust applied (not necessarily full throttle, please note), I pull the prop back to 1900 with the prop lever. It's a small adjustment and easy to do, so this sort of acts like my governor. For my flights yesterday, I did leave it at 1900 as that is a permissible cruise setting (although it is noisy :().Thanks again Fede. Really appreciate your efforts here! As soon as I get further info on the governor, I'll post them here.

[bliksimpie 1]

Thanks fede80, Used your figures and it is absolutely briliant..Awesome mate..!

[FlyinIron406 3]

Hey guys,I haven't really read through this whole thread, but I'd like to try your ideas. I was one of the beta test pilots on this, and find it semi-insulting you say "ask a real pilot how it flies". I guess that's the way of the world. Given, there are many limitations in FSX, but .air and .cfg files can always use tweaking.At cruise at 5000ft, at 17/17, you should see between 130/140KIAS depending on weight. Remember, TAS is a LOT different than IAS.I'm interested in seeing your solutions to the ITT temp. An yes, most operators fly the Caravan full torque and prop. I like it quieter, so I usually have the prop at 1700 in cruise, down to 1600 for descent.Feel free to ask questions, as I check avsim almost daily.

[FlyinIron406 3]

One other speed issue I've noticed was during slow flight.With full flaps, the airplane runs out of trim at 68 KIAS (with default full fuel and passengers/cargo, 2500 feet MSL).In other words, when the autopilot altitude hold is engaged and I reduce power to lower speed, once I've lowered power to the point where I see 68 KIAS the autopilot has advanced the trim wheel fully forward (19.5 deg) and any further reduction in power means the airplane will lose altitude.Makes the last moments in IFR approaches difficult and seems wrong. The stock Caravan certainly doesn't have this behavior - the autopilot can hold altitude at much lower speeds before it runs out of trim.I don't believe that has anything to do with engine power. I suspect drag, but more testing will be required. For example, it could be all the gauge calibrations are way off, or she flies like she's 2,000 pounds too heavy. Could be a lot of things.You all may want to fool around with some slow flight to check the airplane's behavior at that stage of flight. It sure doesn't feel right, but I'm not a pilot, so I'm just basing this on the way other FSX aircraft perform.

The real airplane gets super spongy below about 90KIAS, especially with heavy loads. Also, AP use is prohibited below 80KIAS. And, yes, in real life you do run out of trim...the speed may be off just a touch, but it is normal to run out of trim, especially in stalls. I just did my recurrent, so it's fresh in my head!IFR approaches for the most part, should be flown at 120KIAS, 11torque for level flight/700 for descent, and 10 deg flaps (you can use 20 deg, speed will be roughly 110 KIAS). I have only flown 2 instrument approaches that you would ever need the excuse to do flaps 30, and then even you'd be looking for 95KIAS.It's been my experience that the real airplane never actually flies at the perfect numbers set forth by the POH, when the plane was manufactured 30 years ago, at sea level standard day with no wind and perfect conditions and brand new everything, with a 20,000hr test pilot.For sure I'm willing to try your edits in this post though.

Gents,One of the problems I've been looking at is that the ITT goes so high that you can't set the torque properly.I do think parasite drag was set a bit too high, but also the turboprop engine power scalar was too low. There's a sweet spot to be found, where the torque limit can't be achieved, and the PIH gives us that...above 42^oC at sea level. So, I'll diddle with the power scalar until I get it to the point where ITT goes over 805^oC at sea level when takeoff power is set.Meantime, the ability to set torque values properly will help determine the drag scalar value.

At full takeoff power of 1865ft lbs, you will never typically see 805C at Sea Level. I fly at higher temps than standard, and typically see 700˚C on takeoff, sometimes up to 730. Our company uses 710 for all purposes. I have the POH at hand if you'd like to know more. I've never seen over 750, unless on starts.

[FlyinIron406 3]

As you mentioned flaps, don't you think it's a bit too litlle the ballooning effect? I see there's a little ballooning above 140 KTS when setting the first notch, the other two nothces increase only the drag (it seems). Do you think it's correct? Just wondering.Cheers

The real airplane does balloon substantially with addition of flaps, it's not like a nice airliner with auto compensators and such. My company uses the flap speeds 140 for 10, 125 for 20, and 100 for 30. 10 deg is the most dramatic, with 20 not far behind. At 100 KIAS for flaps 30, you actually notice a lot less lift, but drag rise considerably.Typically, you have to give 2 to 3 good rolls of nose down trim to counteract the addition of flaps (conversely, in the climb raising flaps you need the opposite...or your climb will disappear).

[FlyinIron406 3]

I know Kurt, but I go as far as I can, I can't reprogram FSX! :)Ok guys, I have a solution to my latest problem. Unfortunately there isn't a single value to be changed, we have to use the airfile editor. Line 1548, the very last one, atmospheric density on shaft torque (why the things I need are always at the bottom? :) ). It's a graph, X Y simple one. You'll see the X axis is locked, leave it locked. Work on the Y. I'll make a sort of table below with the X value and the corresponding Y value to be changed.X= 0.00204 / 0.00175 / 0.00149 / 0.00126 / 0.00114 / 0.00089Y= 0.99 / / / / 0.94 / / / / 0.81 / / / / 0.74 / / / / 0.69 / / / / 0.61I checked until 20000 feet. Believe me, you won't go higher with this plane, but it should work higher too. Things I said earlier are still valid: when you see you are at full throttle, don't decrese the RPM unless you are looking for a slower cruise with lower settings of both torque and RPM. I can't reproduce the increase in torque due to the reduction of RPM...This should be ok. I'll wait for your resultsCheers

Great work on this FEDE and others. Again, FSX has many limitations (and more so on turboprops) that are impossible sometimes to work around. I know FS has never modeled the changing of torque when prop pitch changes (even in pistons). Also, they modeled the sound off of the power only, when in props it's usually only on the prop you hear sound changes.

[FlyinIron406 3]

That's good news guys! You know, it took me so long I didn't even have the time to make a complete flight yesterday night, soooo tired...! But the important thing is the end result, now we can all enjoy this beauty, can't we?For the prop governor, I think I may have the tweak for it, but I'm not sure whether to implement it or not. I mean, you takeoff at full power, ok? Then you reduce the power and throttle, but climb settings are 1865 tq and 1900 RPM. So this would mean that if 1900 was the maximum rating you should climb with the prop full fine (and cruise as well), and as far as I know it's never like that. It sounds like a torture for the engine! :) Maybe this plane is different and it is supposed to be this way, but I'd rather leave it the way it is right now.Maybe Glen, you can ask your friend when you meet him about this, and let him tell you how the real one flies. There are some "secrets and tweaks" only a pilot flying it knows.. ;)Guys, I thank you for your time, reports and checking. Hopefully now I can make a flight! :)CheersFede

Hey Fede,The normal procedure is to takeoff flaps 20, full torque to the limit of ITT (so, typically 740, but up to MAX TO power of 805 for five mins if you need it [believe it or not, you can actually run the engine up to 2400 ft lbs for 20 seconds), and 1900RPM. Climb is done with 1900RPM, and full torque. Typically in the climb, you can increase the power a few times to max torque again (until you temp out). In the Caravan, you will temp out way before you torque out. In cruise, many operators, especially on short hops of under an hour, will cruise at 1900RPM and the max torque allowed for it in respects to temp and altitude. I know some people that usually fly full torque and prop everywhere, even in the descent. I typically fly full torque and prop to cruise, and then 1700 ft lbs and 1700 RPM for cruise, and in descent I usually go to 1600/1600 and let power increase to max torque settings for altitude. Below 2000 feet typically, you can use full torque up to 1865 (and if you feel the need, 1970 for less than 1900RPM).I hope this helps. Feel free to PM me if you have a few questions or what have you. I'm off the next 2 days so I'll be around. And should be able to answer some of them.BTW, I'm not affiliated with Carenado, but I did beta test this and am willing to help you or give you insight. Thanks everyone for your work on fine tuning.

[FlyinIron406 3]

Hi,I also offered some opinions on these issues in this post in the general section:http://forum.avsim.net/topic/294087-how-about-that-first-flight-in-the-carenado-208b/page__gopid__1819178#entry1819178Again, feel free to PM me with questions if you have them in regards to operations and such. I do not work for Carenado, but I did help with the test and I do fly these planes 80 hrs monthly :(