Confusion Over Cargo Weight Of DC-4s. C-54s, and Carvairs

I've been searching for suitable new textures for this classic workhorse.

I'm mainly looking for Alaskan and Canadian cargo textures and I note that you've added .... (with the addition of the CF-IQM paint).

Would you be so kind as to point me in the right direction for these textures please.

Thanks,

Pete
 
srgalahad said:
This is a flight in a STOCK FR C-54G/R5D (with the addition of the CF-IQM paint).
Click to expand...

Thank you for your kindness in sparing time from your busy schedule to make testing flight.

srgalahad said:
Take off Max power, 0 flap, gear up thru 100 agl.
Click to expand...

Are you saying that you took off with max power and zero flap or are you saying that you retracted flap and gear at 100 AGl?


srgalahad said:
Base weight + 600# crew, 20000# load + 6369# fuel. = 66,356.9 lbs at takeoff.
reduced to 35" / 2350 rpm and set autopilot for 7000 ft and 800 fpm
Speed reduces from 155KIAS to approx 140 KIAS at 4000 so climb was reduced to 600 fpm

Level at 7000, power set to 30" /2150 rpm and once speed stabilizes - 185 KIAS (200 KTAS)
Click to expand...

I wish I could achieved those figures!! Maybe it works for you because you used R5D model base and I used DC-4 and Carvair model bases unless somebody tells me model bases do not make difference.

Did you make that flight test before Mike made modifications to aircraft.cfg or after he made modifications and gave the revision to you to test?

srgalahad said:
Also, if you are trying to recreate Buffalo flights, there is NO need to go for higher altitudes in the DC-3 or DC-4. The Minimum Enroute Altitude on V321 between HY & ZF is 3000' so the northbound leg could be filed at 3000 but more likely 5 or 7 and no higher..
Click to expand...

Strange I thought Buffalo Airways always uses 9,000 to 10,000 ft for CYHY to CYZF and back routes. I remember from seeing NWT ICE PIlOTS episodes.

Once again, thanks for your very kind assistance and for your flight testing.

Maybe I should test R5D model base to see if I can do the same thing you did unless Mike tells me that all model bases in the Flight Replicas DC-4 package have same aircraft.cfg. However, I think DC-4 and Carvairs should do better in performance to match real world operations.


Regards,

Aharon
 
After finishing few flights abroad FR Carvairs and FR DC-4s, I am going this week make a testing flight using R5D model base (C-54G) to see if I can replicate amazing successful flight that Srgalahad did as seen below. Hope it will work for me!!! Willl let all of you know the results

Regards,

Aharon

srgalahad said:
Base weight + 600 lbs crew, 20000 lbs load + 6369 lbs fuel. = 66,356.9 lbs at takeoff.
reduced to 35" / 2350 rpm and set autopilot for 7000 ft and 800 fpm
Speed reduces from 155KIAS to approx 140 KIAS at 4000 so climb was reduced to 600 fpm
Level at 7000, power set to 30" /2150 rpm and once speed stabilizes - 185 KIAS (200 KTAS)
Click to expand...
 
Originally Posted by srgalahad Base weight + 600 lbs crew, 20000 lbs load + 6369 lbs fuel. = 66,356.9 lbs at takeoff.
reduced to 35" / 2350 rpm and set autopilot for 7000 ft and 800 fpm
Speed reduces from 155KIAS to approx 140 KIAS at 4000 so climb was reduced to 600 fpm
Level at 7000, power set to 30" /2150 rpm and once speed stabilizes - 185 KIAS (200 KTAS)
Click to expand...

Okay okay I finally got to test R5D model base with Buffalo Airways repaint and loaded it up with same weight load factors as stated by Srgalahad seen above in his quotation EXCEPT I set the crew as 400 lb, not 600 lb unless I wanted to hire sumo wrestlers or football linebackers as pilots.

I regret that I am unable to recreate the climb rate and speed successes of Srgalahad.

For my flight from CYHY to CYZF, the R5D plane was unable to sustain 800 fpm at 155 KIAS speed and I was forced to use 200 fpm in order to maintain stable 130 KAIS speed. If I use 400 or 500 fpm, the speed would go down to 120 KIAS speed. I gave up climb at 3,000 ft and built up speed to 145 KIAS to resume climb to 5,000 ft which reduced the speed to 130 KIAS although I prefered 7,000 ft to 10,000 ft cruising altitude which is not going to happen for me.

And the cruise speed after reaching and leveling at 5,000 climbed to top speed of 154 KIAS or 170 mph with full throttle power which fell short of 185 KIAS speed that Srgalahad enjoyed cruising in his same plane. Also 154 KIAS speed at full throttle power is not realistic as full throttle power is supposed to produce top speed of 200 KIAS or 75 percent throttle power is supposed to produce 185 KIAS or much much reduced throttle power is supposed to produce 145 KAIS speed for Buffalo Airways planes.

I am okay with 154 KIAS as it is realistic speed for Buffalo Airways planes which usually cruise at 140 KIAS but but but top speed of 154 KIAS is not realistic for R5D model or DC-4 model or Carvair model as in real life, I am sure those planes in their hayhey glory days as brand new planes cruised at much higher speed especially air force C-54s!!!!

Either I am doing something wrong or aircraft.cfg in all model bases need to be modified If I was in real US air force with my climb and speed performance, I do not think I would be successful for Berlin Airlift missions and air force generals would likely to scream at me for lousy climb and speed performance.

Can anybody help me in solving the mystery of climb rate, climb speed, and cruising speed, please? Carvair is kind of fun to fly. So R5D with Buffalo Airways is too. And I do not want to give up and do not want to put the plane in permanent hangar storage.

Thanks,

Aharon
 
Sorry if I missed it being addressed above, but are you using manual mixture settings and leaning the mixture accordingly?
 
expat said:
Sorry if I missed it being addressed above, but are you using manual mixture settings and leaning the mixture accordingly?
Click to expand...

Expat,

No need to apologize. I am using 100 percent fuel mixture switches (4) unless somebody tells me that this causes low KIAS speed and I should reduce mixture to increase KIAS speed??????? If so, how many percent mixture?

Regards,

Aharon
 
If you are not using the "auto mixture" setting, you will find particularly with old propliners a substantial power loss/increase by adjusting the mixture, along with MAP and prop pitch/rpm throughout the flight profile. I do have the FR C-47 but don't recall how mixture sensitive it is vs the Calclasssics DC's and Connnies which are quite so. Others here can elaborate more expertly I am sure.
 
Hi all
In real life it is a fact that you have to lean the mixture as you go higher to maintain the best possible fuel-to-air ratio in the pistons and therefore the bigger explosion (hence power), there are a number of other factors , but lets not muddle at this point.

If you allow for auto mixture in FSX (there is a tick box for that in the realism settings) it might be possible to see the difference, otherwise, I found a gauge that does that in the Cal-Classic forum:
https://calclassic.proboards.com/thread/7825/fs9-fsx-automixture-gauge

Or you could also use "Real engine 1.4", which you can find here:
https://www.sim-outhouse.com/sohfor...-FSX-RealEngine-Aircraft-Limitations-v1-4-zip

Hope it helps

Saludos
 
You asked before and I don't think I answered. In my sim the FR model is installed as downloaded. No mods, no tweaks. I can see no reason within the model that there should be any difference on a different computer. Having said that, there are numerous things that can make a difference: calibration of controllers can limit how the sim is controlled (full-forward may not be full throttle for example); loading of the a/c -weight and balance affect trim and attitude affects drag; I don't know if FR included drag for the cowl flaps but I have seen models that do to the tune of 5 kts or so. As discussed above, if you are using manual mixture it's essential to have it set correctly. (My flights were with sim Auto-mixture enabled)

That's why I recommend (while testing) that you use AFSD to be able to monitor the various parameters accurately as you go. Again, power and IAS will drop with increased altitude so do your testing at/near sea level to start and (with AFSD) monitor/record TRUE airspeed - once you get close to the 'published' numbers, try higher altitudes but remember that power and IAS will drop as you fly at higher altitudes - check the TAS.
One particular thought - why try to climb at 155 Kts (178 Mph!)? that is an exceptionally high airspeed . Older aircraft generally climbed at much lower IAS than their cruise/max speeds (see below)

I was able to find an Operating Manual for Resort Airlines DC-4B ( appears modified from Chicago & Southern manual). The charts are a bit difficult to read (older photocopies) but you can glean a lot if you squint and interpret. It also has comprehensive checklists and training hints that fill in more details.
Here are data pulled from the pertinent sections:


Weight: MTO 70,000# MLW 61,000#

Wright Cyclone R1820-C9HD 6.8:1 (Fuel 100/130)

Ratings:
T/O 1425 HP 51.5" MP 2700rpm SL 5 min.
Normal 1275 HP 46.5"MP 2500 rpm SL
Normal 1275 HP 45.5" MP 2500rpm @3500 ft
Take off flaps 15*

Page 21/22 of the .pdf
"Performance data shown... based on the following speeds:
Climb speed: Flaps up (Max continuous power) 138 MPH (that's 120 Kts IAS)
other data listed for engine inoperative

Page 34------------
True Indicated Airspeed 138MPH
Gear up, Flaps retracted Max. Continuous power

Reading from chart:
SL 73,000# 950 fpm -- 2000ft 925 fpm --- 4000ft 900 fpm --- 5000ft 825 fpm

Page 61:
..."it is possible to create a stall condition by raising the flaps at airspeeds below those necessary to maintain flight for reduced flap extension."
-----------------------------------------------------------------------------------------------------
Note: with a high-drag airframe like this even small deviations from the above speeds/attitudes can have surprising (and negative) effects on performance. Speed takes quite a while to recover if lost.

https://aviationarchives.blogspot.com/2016/07/douglas-dc-4-operating-manual.html
A copy of the Douglas DC-4 (C-54B-DC) Operating Manual from Resort Airlines, dated April 15, 1951. Credit: Irfan S. Hokan Collection Click here to download manual in PDF form (12.3 Megs)
 
Expat, Ascua, and Srgalahad,

Thanks all for your kind words and answers.

srgalahad said:
\"Performance data shown... based on the following speeds: Climb speed: Flaps up (Max continuous power) 138 MPH (that's 120 Kts IAS)
Click to expand...

120kt KIAS is NORMAl speed for climb?? I thought it is very abnormal as I had been averaging 130kt KIAS during climb at 200 fpm!!!!! If I tried 400 fpm or 800 fpm, it would dip down to 120kt KIAS which made me afraid that the plane would crash! Is 120kt KIAS normal for climb speed???

Flight Replicas has informed me that it is NOT my fault or NOT my flying skills. Flight Replicas said it is fault of FSX Deluxe with SP1 and SP2 because DC-4 is designed for FSX Acceleration or FSX Steam or FSX Gold. And DC-4 does not work well in FSX Deluxe with SP1 and SP2.

I might disagree with Flight Replicas because FSX Deluxe with SP1 and SP2 is same as FSX Acceleration and I think it is MY fault because I might have been using WRONG level settings for propeller control, mixture, throttle, power, and fuel even though I managed to successfully complete the flights.

Can anybody show me screenshots of cockpit panel showing precise settings at percentage (70 percent or 80 percent or so as indicated by window bubbles when mouse is hoveringover levels) of fuel, mixture, and throttle levels in middle of cruising flight action so that I can study to see what I did wrong during my successful flights although slower KIAS speed. I think I am not supposed to set mixture level at 100 percent during flights.

If Srgalahad can do this performance indicated below, then I should be able to do too!!

srgalahad Base weight + 600 lbs crew, 20000 lbs load + 6369 lbs fuel. = 66,356.9 lbs at takeoff.
reduced to 35" / 2350 rpm and set autopilot for 7000 ft and 800 fpm
Speed reduces from 155KIAS to approx 140 KIAS at 4000 so climb was reduced to 600 fpm
Level at 7000, power set to 30" /2150 rpm and once speed stabilizes - 185 KIAS (200 KTAS)
Click to expand...

Regards,

Aharon
 
Okkkayyyyyyyyyyyyyyyyyyyyyyy

Made another testing flight abroad R5D!!!

Had it climb after take off and flew it using different methods which was to reduce propeller control levels to 70 percent and reduce the mixture levels to 70 percent.

That improved the climb speed from 130 kt to 140 kt, improved the climb rate from 200 fpm to 400 fpm, and improved the cruising speed from 154 kt KIAS to 166 kt KIAS.

But that falls short of 180 kt KIAS cruising speed and 800 fpm climb rate.

Mmmmmmmm what else should I do to get to 180 kt KIAS cruising speed and 800 fpm climb rate??

Regards,

Aharon
 
Hi Aharon,

Why are you talking about percentages? I have this plane as well and it flies by the number.
I always use the manual and follow the given procedures:

Take-off: 50"manifold / full prop / mixture auto rich (85%)

when possible reduced to 40" / 2550 RPM and climbing at 500 fpm

Climb: 35" / 2350 RPM / mixture auto rich

Cruise: 30" / 2250 RPM / mixture auto lean

Good luck,

Marijn
 
Hi Aaron, I do not know if you did it already but just in case...

When you are flying this sort of aircraft, it is important to get them in the correct attitude (angle of attack, AoA) to get the less drag and the best speed.

Basically, when you get to the desired altitude, do NOT reduce the engine settings, let the aircraft accelerate on its own, then, once the maximum speed is attained (or the target cruise speed is well exceeded), reduce the engine settings to cruise.

The aircraft then will decelerate on its own and keep the best attitude and speed for those settings.

This is so because as you climb you have a higher AoA than at cruise and you fly slower, which creates some drag. By accelerating you reduced the AOA and the drag induced by this will reduce and then as you reduce your settings it will slowly increase to the correct values on its own.

In another words, at cruise settings you may not have enough power to counteract the drag caused by the AoA, so go past that point and then reduce so when everything stabilizes you are in the optimal (ish) position. :peaceful:

The explanation is a bit more complex than that, but if you haven't give it a try and tell us.

Saludos
 
Hi Aharon,

The above method and flying to 500 ft ABOVE your assigned altitude, set RPM and manifold pressure to cruise and decent to your assigned altitude will give the same result and a correct AOA.
(but all of this is also described in the manual of course).

brgds,

Marijn
 
You must log in or register to reply here.
Back
Top