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AJW
09-07-2003, 10:46 AM
I did a search using "DC-3 maximum range," but found no definitive information on the topic. When I researched elswhere, for example in the Sybex "Microsoft Flight Simulator 2004, A Century Of Flight" manual, it gives the DC-3 maximum range as 1,845 NM (2,125 MI). Nevertheless, the default Fs9 DC-3 doesn't give even half that distance. That is not realistic. Why this disparity -- and has anyone come up with a proven remedy?

In the early days of WW-II, the ATC used to fly DC-3s across stretches of the North Atlantic, for example, that would have gotten the pilots drowned in the default Fs9.

Anthony

FearlessTower
09-07-2003, 11:45 AM
You are correct, the default DC-3 does not have anywhere close to the range that it is supposed to. It also does not matter what you do with the throttle/prop/mixture settings....you're still going to get wet crossing the Atlantic.

I believe the problem lies in either the fuel consumption rate or the fuel tank quantity/capacity. I suspect it is the fuel burn rate, but since I don't have a copy of the DC-3 manual (only have the checklist) I can't confirm this or determine what it should be. If anyone knows what the burn rate should be, please let us know.

Andrew

AJW
09-07-2003, 12:41 PM
Andrew, I suspect it's the fuel quantity. No realistic burn rate change will more than double the range given in the Fs9 DC-3. As you did, I leaned the mixture and cruised at higher, more efficent altitudes.

Hey, wait a minute! Maybe you want to double-check me on the mileage of an over-the-water flight I just completed from KEFLAVIK (BIKF) Iceland to NARSARSUAG (BGBW) in Greenland. I used the GPS to plot the course, and used the AP to manually adjust the heading. (I also sped up the rate to 8X over the open sea). I forget how many miles the GPS said the flight was, but I'm almost sure it was more than the default 845. Nevertheless, when I landed at BGBW I still had about 100 gallons left.

Anthony

flyingtim1
09-07-2003, 01:32 PM
this is what i did and works for me,i changed the fuel flow in the dc3 cfg file its under
GeneralEngineData
xxx
xxx
fuel_flow_scalar=0.46 note default is 1.00

with no weather or wind and using a climb rate of 600fpm and 130kias climb speed at fl120 i get about 1850km range with cruise speed of 160knts.
not sure if iam done tunning with it but its lot closer than default
tim

FITZY
09-07-2003, 01:48 PM
For what its worth, the following is from the USAF Museum web page on the C-47:

SPECIFICATIONS
Span: 95 ft. 0 in.
Length: 64 ft. 5 in.
Height: 16 ft. 11 in.
Weight: 33,000 lbs. loaded
Armament: None
Engines: Two Pratt & Whitney R-1830s of 1,200 hp. ea.
Crew: Six
Cost: $138,000
Serial Number: 43-49507
C/N: 15313/26768
Displayed As: 43-15174
PERFORMANCE
Maximum speed: 232 mph.
Cruising speed: 175 mph.
Range: 1,513 miles
Service Ceiling: 24,450 ft.

http://www.wpafb.af.mil/museum/modern_flight/mf3.htm

Guttural Roar
09-07-2003, 02:13 PM
I have a copy of the C-47 Pilot's Manual. Here is a scan of the C-47 Long Range Level Cruise Fuel Chart. Sorry for the lack of clarity - I don't have OCR software. Hope you can read it.

Carey

http://members.cox.net/flyingfortress/c47_range.jpg

AJW
09-07-2003, 05:56 PM
>I have a copy of the C-47 Pilot's Manual. Here is a scan of
>the C-47 Long Range Level Cruise Fuel Chart. Sorry for the
>lack of clarity - I don't have OCR software. Hope you can
>read it.
>
>Carey
>
>http://members.cox.net/flyingfortress/c47_range.jpg

After seeing this chart and other references, it is clear that the Fs9 default DC-3's fuel capacity is much less than the capacity of "real world" DC-3s. Where the prototypes could go aloft with a maximum of 1,200 gallons, if needed, the Fs9 DC-3 has a mere 604 gallons. There's the difference in maximum range: half as much fuel.

Anthony

elleresort
09-07-2003, 07:26 PM
"this is what i did and works for me,i changed the fuel flow in the dc3 cfg file its under
GeneralEngineData
xxx
xxx
fuel_flow_scalar=0.46 note default is 1.00
with no weather or wind and using a climb rate of 600fpm and 130kias climb speed at fl120 i get about 1850km range with cruise speed of 160knts.
not sure if iam done tunning with it but its lot closer than default
tim"

can anyone verify that this works...im taking a dc-3 around the world...and i need all the distance i can get!

James Burns
KBUY - World Tour 2003

AJW
09-07-2003, 08:01 PM
>
>can anyone verify that this works...im taking a dc-3 around
>the world...and i need all the distance i can get!
>
>James Burns
>KBUY - World Tour 2003

Jim:

Good luck with the around the world flight. I edited the file using your 0.46 factor, and am now flying from Narsarsuag, Greenland, to Gander, Newfoundland. As I recall, the GPS calculated the original miles at about 850. I took off with a full load of fuel (604 gallons). I'm cruising at 10,000', 28"MP, 2,100 RPM, mixture leaned to 45%. I just guessed at the mixture, lacking any specific DC-3 reference on mixture settings at altitude. The cylinder head temperatures are in the bottom of the green with the 45%.

If your estimate of maximum range using the 0.46 modification is accurate, I should arrive with slightly less than half fuel remaining. If it is not accurate, and the default maximum range applies, I either may arrive on fumes, or get wet.

Anthony

AJW
09-08-2003, 06:45 PM
OK, I used the 0.46 modification to the fuel flow suggested by Tim, filled the tanks (604 gallons) and flew a 797 mile flight. I cruised at 10,000', set the power at 28"MP, props 2100 RPM, and leaned the mixture to 38%. My payload was 4,000 lbs. When I landed at my destination and shut down the engines, I had used 241 gallons of the fuel.

According to my calculations, under the SAME weather conditions, cruising altitude, payload, fuel load and power settings, this modification will give the DC-3 a maximum range of 1997 miles, if you just keep flying until it runs out of fuel and falls out of the sky. It seems, therefore, that the modification does give the Fs9 DC-3 the approximate maximum range of the real life prototype. That should help Jim on his around the world flight. Keep us posted on its progress Jim.

Anthony

flyingtim1
09-08-2003, 08:50 PM
Been doing some more testing and it looks to like fs will let us use the 3rd digit......so now iam using 0.465 for the fuel flow.
ran some test flts at fl100 and a cruise speed of 185mph and iam sure close to 1845nm range.
now to work on prop,mix and add weather and see,iam thinking of joining jim and doing a round the world.
good luck jim,lot of water and desert to fly over hehe.
tim

FITZY
09-08-2003, 09:38 PM
This is perhaps a foolish question, but somebody has to ask it. I gather that fuel quantity, ie tank size and/or quantity cannot be edited? I thought I saw a file in the library that did just that.

flyingtim1
09-08-2003, 10:18 PM
No such thing as foolish question in fs,one never stops learning what makes fs work........yes fuel quantity can be changed,that also is in your aircraft cfg file under fuel.
there are a lot of variants with dc3's and the one in fs9 had 604 gal tanks,so what we are trying to do is get the range to match that amount of fuel. Iam not sure what happens if you increase the tank size to say....2000gals,could be the fs flt model will now be overweight plane that wont even take off. It just seems to me if we adjust the rate of fuel burned we will have a plane that is like the real thing.
I do remember reading long time ago how they carried 55gal drums of fuel to make the alantic crossing durning ww2.
hope this helps
tim

Crazyw
09-09-2003, 06:06 AM
Try this airfile in Avsim (airfilec47a.zip)it changes a Dc-3 to a C-47 with fuel and engine specs. I did change the fuel burn to 0.46 and also the props to 11.5 ft and cyl cu. in. to 130.71 as per a really good dc-3/C-47 web page. Got a really good fuel/distance rate increase. 147 KIAS at 10,500 ft w/ 1850 rpm, and 31 in. mp, 33% mixture. made 1200 miles on 260 gals. I will also be checking some old volumes of JANES I have access to on the C-47 to make sure of specs.Only prob I have now is still ground taxi turns. real throttles would be so great!

Braced
09-09-2003, 06:58 PM
"Only prob I have now is still ground taxi turns"

check out this fix:

http://www.flightsim.com/dcforum/DCForumID21/4999.html


It will make it steer with the joystick. I know, it's not realistic! but neither is a single throttle and twist grip joystick!

Give it a try, it'll enhance your DC-3 flying.

Crazyw
09-10-2003, 10:35 AM
copied JANES 1949 data.
they give max range of 1,510 miles with 822 gal of fuel/ 2 main tanks at 210 gals each and 2 aux tanks at 201 gals each.
Recommended cruise speed of 185 mph at 10,000 ft w/ fuel consumption of 88-95 Gals per hour. guess I will have to play with burn rate to get it right. cylinder CU/IN should be 130.71428. Props on data sheet show 11 ft 6 in. dia.

AJW
09-10-2003, 10:56 AM
>Been doing some more testing and it looks to like fs will
>let us use the 3rd digit......so now iam using 0.465 for the
>fuel flow.
>>tim

Of what real value is the third digit? Three places past the decimal is THOUSANDTHS! To change from 0.46 to 0.465 is an almost umeasureable 5/1000 adjustment of the fuel flow. In fact, it will probably be just as easy to round off the initial adjustment to 0.50 and leave it there.

If a modification does not provide VISIBLE, FUNCTIONAL improvement, why bother with it?

That's why I don't understand the logic of the guys who are obsessed with tinkering and tweaking until they can achieve a zillion FPS. Why?? Is it just to get bragging rights?

Anthony

Scottharrod
09-10-2003, 11:09 AM
Hey guys. Sorry, not trying to hijack the thread. This is along the same lines.

The Lear 45 seems way off the other way. I'm not in front of my game PC so I don't know exactly but I think the range for the Lear given by fs9 is 2000 miles. I can easily load it up and fly 3300 miles.

flyingtim1
09-10-2003, 01:10 PM
well maybe this will help, i use this gauge and it seems to work in fs9 even though its a fs2k2 gauge........RKG_fuelstat.gau,by Robert K. Guy,version 2.00
It has some really nice features that make sim flying easy,read the readme and you wont have any problems with it,i have yet to find a plane it wont work in.
Iam not having much luck getting correct spec's for fuel flow of the fs9 dc3,but thats half the fun simming i think
tim

elleresort
09-11-2003, 04:54 AM
Hey you guys thanks for the support

i just updated the paint. and i posted a picture

http://www.flightsim.com/dcforum/DCForumID8/30830.html


James Burns
KBUY - World Tour 2003