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

  1. #1

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

    Shalom and greetings all my pals,

    I am totally perplexed by pound weight of cargo load of DC-4s and Carvairs in both freeware CalClassics and payware Flight Replicas model bases.

    According to real world Buffalo Airways website, their DC-4 can carry 20,000 pounds of cargo load.

    In the payware model base, I tried to take off using both DC-4 and Carvair with 50 percent fuel load using full cargo load of 9,500 lbs as seen on this figure below which failed to climb after shaky take off and crashed on ground.

    max_number_of_stations = 6
    station_load.0 = 950, 10, 0, 1
    station_load.1 = 2500, 2, 0, 1
    station_load.2 = 2500, 1, 0, 1
    station_load.3 = 2500, -2, 0, 1
    station_load.4 = 1000, 5, 0, -1
    station_load.5 = 1000, -10, 0, -1

    I was forced to slash cargo load by half from 9500 lbs to 4750 lbs and reduce fuel load from 50 percent to 40 percent which barely got my payware plane into air, climbed very very slowly, and cruised at too slow speed 160 kt.

    By contrast, for years years years I have NO problem flying CalClassics DC-4s and C-54s cruising at 200 kt using 8,200 lbs of cargo load and 50 percent fuel load as seen on the cargo load data beloe

    max_number_of_stations=2 ;loaded symmetrically v CoG
    station_load.0=800,0,0,0 ;4 crew + bags
    station_load.1=7400,0,0,0 ;max cargo payload with max fuel
    station_load.2=800,0,0,0 ; cargo


    My questions are: why are both freeware and payware DC-4s/C-54s as well as payware Carvairs have top cargo load of 9,500 lbs for payware addon and 8,200 lbs for freeware add on when the real world Buffalo Airways say their DC-4 can carry 20,000 lbs in full cargo load?? And why are DC-4s/C-54s/Carvairs in the payware model base cannot go above 160 kt in speed when in real life the maximum should be 220 kts and cruising should be 190 kt???

    And why do CalClassics DC-4s have normal climb while the payware counterpart has painful slow climb??

    Am I doing something wrong??

    By the way, Carvairs in real life can carry 19,000 lbs of cargo load yet I could not climb with 9,000 lbs of cargo load which is set as maximum cargo load for payware add on!!


    Regards,

    Aharon

  2. #2
    Are you using FSX or P3D version?? My P3D4 version has an ASI calibrated in mph vice KIAS. That is a 15% difference in what you use if flying KIAS (which I always prefer). Example: 140 KIAS is about 160 mph indicated

    C-54 and DC-4 production airplanes have weight and engine combinations that are all over the map. In addition there are many approved mods throughout their life, and military specs were higher than authorized by FAA certification in many cases.


    You likely know that cargo capacity is governed by max ZFW minus empty operating weight. The specifics in the FAA cert are a little obscure in their data - ZFW was not a very concrete parameter in the days that these planes were designed.

    If you REALLY want to get tired of reading, look at the FAA certification data "AIRCRAFT SPECIFICATION NO. A-762" -at the back is information pertinent to all models. You can find it here: https://rgl.faa.gov/Regulatory_and_G...e?OpenFrameset

    This will give you some insight. I think the FR model is roughly based on the C-54B - they are not very specific.


    Of course this does not answer your question regarding the performance in your sim - that is a different matter.
    Last edited by Mike71; February 3rd, 2021 at 14:14.

  3. #3
    Hi, Aharon! Can you give us some more information? Specifically, we'd need...

    1) What was the aircraft's takeoff weight in each situation?

    2) What takeoff flap setting did you use?

    3) What takeoff, METO, and climb power settings did you use in each aircraft?

    When an operator like Buffalo talks about their aircraft's "maximum payload," they're usually telling you the Maximum Zero Fuel Weight (MZFW) minus the Basic Operating Weight (BOW). An airplane can only carry "stuff" up to the aircraft's MZFW. All weight above that must be fuel. Does that mean the aircraft can always operate at MZFW? No, since the MZFW is a structural weight only, and doesn't consider takeoff and climb performance or fuel requirements.

    For example, the SAA Museum lists their DC-4's MZFW as 60,700 pounds. For our purposes let's assume that's a standard weight across all your DC-4s. With a payload of 20,000 pounds, that would make the BOW 40,700 pounds. The Flight Replicas model uses 40,000 pounds, and if you're using the JBK v3.0 freeware version, the BOW is 43,176 pounds. Both those weights are believable based on the facts available.
    America never stopped being great.

  4. #4
    Agree, nagpaw.

    wrt ZFW, some airplanes, and especially some of these WWII/later long range props, had ZFW's that varied considerably based on fuel tank installation and tank loading - just to confuse the issue. The FR model I have is set up as an 8-tank version. I pick some representative max weight (73,000 lbs) and station load values from various real life sites and FAA data, then mod the aircraft.cfg file to reflect what I choose. You have to be careful regarding cg position and engine version max power when doing this, however.

    Also realize that the fuel and payload values in the aircraft.cfg file do not have to add up to max ramp or max takeoff weight - they often exceed max weight. The FS pilot has to adjust the loading to stay within limits. This is typical of real life as well.

  5. #5
    Thanks all for very kind answers

    Quote Originally Posted by Mike71 View Post
    Are you using FSX or P3D version??
    I am using FSX Deluxe with SP1 and SP2

    Quote Originally Posted by nagpaw View Post
    Hi, Aharon! Can you give us some more information? Specifically, we'd need...

    1) What was the aircraft's takeoff weight in each situation?

    2) What takeoff flap setting did you use?

    3) What takeoff, METO, and climb power settings did you use in each aircraft?
    Answer for first question is that I have to make another flight to get you answer. Sorry about that

    Answer for second question is flap one in hope you are not going to scream that I am using wrong flap setting I do not want to use flap two for fear of slowing down the plane during take off run, take off, and climb however I use 2.5 percent trim setting

    Answer for third question is that the answer is same as first answer to first question. Sorry about that.

    Quote Originally Posted by Mike71 View Post

    Also realize that the fuel and payload values in the aircraft.cfg file do not have to add up to max ramp or max takeoff weight - they often exceed max weight. The FS pilot has to adjust the loading to stay within limits. This is typical of real life as well.
    I am aware of that which is why I used 50 percent fuel load and full cargo load of 9,500 pounds (to recreate flight carrying maximum number of cars) on Carviar. That did not work for me as it crashed few seconds after take off and climb. So I reduced to 40 percent fuel load and cut the cargo payload to half to 4,750 lb which is NOT realistic because Carvair can carry more cars than 4,750 lbs and that barely barely got me into air with painful slow climb while not allowing me to go above 160 kt speed during cruising speed.

    What about 160 kt cruising speed? Is that realistic?? Or wrong?? I used full throttle power (100 percent) yet it would not go above 160 kts.

    This got me baffled because I looked at history of all past Buffalo Airways flights by DC-4 carrying MUCH heavy load of cargo for much longer flights than I did as seen example below:

    load of 8,000 lb generator for 400 nautical miles flight

    load of 12,000 lb oil rig equipment for 200 nautical mile flight

    load of 19,900 lb drum barrels of crude oil for 200 nautical mile flight

    Am I doing something wrong??

    Regards,

    Aharon

  6. #6
    Quote Originally Posted by Aharon View Post
    Answer for second question is flap one in hope you are not going to scream that I am using wrong flap setting I do not want to use flap two for fear of slowing down the plane during take off run, take off, and climb however I use 2.5 percent trim setting
    You'll never get any screaming from me, my friend! I'm here to socialize and learn from others

    Your understanding is correct. Takeoff flap settings are indeed a tradeoff: lower settings increase the takeoff roll but increase climb performance, while the opposite is true for higher settings. The only thing I would suggest is verifying the actual flap indication. The first "notch" of flaps in one model may be ten degrees while it's only 5 degrees in the other model. Make certain you're comparing apples and oranges.

    I'm assuming you're only seeing an indicated airspeed of 160 knots. What manifold pressure and propeller RPM are you seeing with "full throttle" in cruise? It's beginning to sound more like a problem with your setup than with your technique. Lemme jump into the FR Carvair on my end and come up with some numbers for comparison. Be right back...



    ...and I'm back!

    So here's what I did. I loaded my Carvair up at KTNT with standard weather (15 degrees C, altimeter 29.92" HG). I put 350 gallons in the Left, Left Aux, Right, and Right Aux tanks (an approximate 50% fuel load) and loaded 9,500 pounds of "stuff," yielding a takeoff weight of approximately 58,600 pounds. I set the flaps to 10 degrees (the first "notch"), the cowl flaps at 50%, and enabled auto mixture. Takeoff power was 50" MP and 2,700 RPM. She flew off just fine and climbed at 155 knots/180 mph indicated and 1,000 feet per minute to 2,000 feet MSL with a climb power setting of 38" MP and 2,550 RPM (the top of the MP green band and upper end of the first red RPM arc), 50% cowl flaps, and the landing gear up.

    I leveled at 2,000 feet MSL with 30" MP and 2,200 RPM and closed the cowl flaps. She's rumbling along at 186 knots/214 mph indicated, or 193 knots/225 mph true airspeed. Keep in mind that those power settings I mention are merely "approximate" numbers I made up from experience, and not the real airplane numbers. Your mileage may vary, but only slightly.

    Also note that the FR Carvair's airspeed indicator displays miles per hour instead of knots. Remember that for most purposes ------> mph x 0.86 = knots.

    Try that yourself in the FR Carvair and let us know what you discover. The things to really check are the power settings you're able to achieve and the proper weights and configurations (flaps, cowl flaps, landing gear).

    Again, it sounds to me like a software or hardware issue on your end, which may require reinstalling the DC-4 package. Unfortunately, software issues are where my expertise ends.
    Last edited by nagpaw; February 4th, 2021 at 10:42. Reason: Added test flight data.
    America never stopped being great.

  7. #7
    Quote Originally Posted by nagpaw View Post
    You'll never get any screaming from me, my friend! I'm here to socialize and learn from others Your understanding is correct.
    Thanks

    Quote Originally Posted by nagpaw View Post

    Also note that the FR Carvair's airspeed indicator displays miles per hour instead of knots. .
    wait wait wait it is in mph, not kt?????????? Since when any aircraft has automobile style mph gauge in cockpit??


    Quote Originally Posted by nagpaw View Post
    I'm assuming you're only seeing a indicated airspeed of 160 knots. What manifold pressure and propeller RPM are you seeing with "full throttle" in cruise?
    What I saw in the speed gauge is 160 BEFORE you told me it is in miles per hour, not knot

    And as for manifold pressure and propeller RPM, I am too embarrassed to admit it is in red color above operating limits because I was trying to get to 190 kt cruising speed although I do not think it caused my plane to crash. However, it meant full throttle at 100 percent instead of customary 75 percent for any old iron planes. I tried 75 percent during cruising and speed just dropped to dangerous level so I increased to 100 percent,


    Quote Originally Posted by nagpaw View Post
    So here's what I did. I loaded my Carvair up at KTNT with standard weather (15 degrees C, altimeter 29.92" HG). I put 350 gallons in the Left, Left Aux, Right, and Right Aux tanks (an approximate 50% fuel load) and loaded 9,500 pounds of "stuff," yielding a takeoff weight of approximately 58,600 pounds. I set the flaps to 10 degrees (the first "notch"), the cowl flaps at 50%, and enabled auto mixture. .
    Me too with exactly same load except cowl flaps on engines were at 100 percent since it is summer weather. Is this wrong??


    Quote Originally Posted by nagpaw View Post
    She flew off just fine and climbed at 155 knots/180 mph indicated and 1,000 feet per minute to 2,000 feet MSL with a climb power setting of 38" MP and 2,550 RPM (the top of the MP green band and upper end of the first red RPM arc), 50% cowl flaps, and the landing gear up. I leveled at 2,000 feet MSL with 30" MP and 2,200 RPM and closed the cowl flaps. She's rumbling along at 186 knots/214 mph indicated, or 193 knots/225 mph true airspeed.
    ARRGHHHHHH you are lucky!!!!!!!!!!! Thanks for your extremely kindness to take time from your busy schedule to test the Carvair plane based on same load settings as mine (except cowl flaps). Surprised me that your flight was success and mine was not (crashed onto ground few seconds after take off) Still baffled how you managed that!!! Something wrong with me.

    Regards,

    Aharon

  8. #8
    SOH-CM-2021 MrZippy's Avatar
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    Aharon,

    Shortly after wheels up, be sure to get your Prop RPMs down into the green zone. If you don't, this may happen....as shown with the MJahn C-47 V2

    Click image for larger version. 

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  9. #9
    Quote Originally Posted by Aharon View Post
    --- wait wait wait it is in mph, not kt?????????? Since when any aircraft has automobile style mph gauge in cockpit?? --

    Aharon
    LOTS of planes have ASI's in mph. I hate it, but it is reality. Many military and civilian planes used mph before and during WWII. Today many civil airplanes have ASIs with dual scales. It likely was a result of trying to make novitiate pilots comfortable in flying and not being confused about "knots".

  10. #10
    Charter Member 2017 srgalahad's Avatar
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    An ASI in MPH? Certainly. Until after WWII that would have been common all over and probably the majority - almost all US-built a/c would be so. ASI's usually show whether Kts or MPH clearly on the face.

    A few things to ponder... let's start with the data. Have you referred to the Performance Charts supplied by FR? They are located in the \SimObjects\C-54B folder.

    Always check RPM & MP on the takeoff roll to be sure you really are producing the expected power.
    First tab shows 20* flap T/O speed @60,000# as 90KTS (105 MPH). Flaps 10 might be slightly higher due to less lift available. Next, you cannot, in the DC-4 just pull into a climb from take-off. As soon as positive rate of climb, Gear UP, but don't increase AOA. Let speed build to about 115Kts before raising flap -in steps. This might mean no more than 1-200 ft/min climb rate initially. Yeah, the trees can look big. Also, in summer (>15*C) performance will degrade.

    So, if you now get up to speed and are climbing, reduce power as shown in the charts (Max T/O 2700/50" power is limited to 5 minutes).

    A couple of thoughts about following the Buffalo 'missions' you reference. They were likely flown in winter - well below std. temp. The ones you list above (2-400nm) are probably never above 5000' asl and it's highly probable that were flown VFR so fuel load could be reduced. An hour and a bit out, same back and 45 min. reserve would cut the fuel load to around 1200 US Gal. (30%) Joe was adamant that engines never be abused so it's likely that the numbers used would be from the 'long range' part of the table or higher (Intermediate) out/low back (remember this would be at lighter weight.) -I know this because I heard him explain it to a rookie co-pilot -thru my office window 3 floors above and 200 ft away with words I can't quote in this forum.

    The Carvair (when used as a shuttle across the channel) would have been similar. Speed was not the first metric to be chased. Fuel consumption and reliability were far more important, so it might be reasonable to look at 170-180 KIAS cruise. As well, the hops were short (350 nm or less) so fuel could be reduced with services available at each end. (Southend to Strasbourg - 325 nm - 2:20 on the schedule - average 141 kts) http://timetableimages.com/ttimages/...62/cab62-4.jpg

    Back to the climb for a moment. I rode jumpseat on a (close to) max weight DC-6 trip of about 1000 nm on a hot summer day. 25nm after t/o we were thru 1000 ft, and at 100 nm thru 3500 ft.

    Be gentle. Crew chiefs can be nasty when annoyed.

    "To some the sky is the limit. To others it is home" anon.
    “Anyone who has never made a mistake has never tried anything new.” -Albert Einstein


  11. #11
    Thanks all for very kind words and very kind suggestions.

    I think the problem with my Carvair from the failed first flight resulting into crash seconds after take off and from unimpressive but completed second flight with bizarre 160 kt OR 160 mph reading in speedometer gauge during cruising at 7000 ft is that I might have made TWO mistakes.

    The two mistakes are that I should have set cowl flaps at 50 or 25 percent instead of 100 percent and that I started climb too soon after take off when I was supposed to take off and level off at 200 fpm after take off to gain plenty of speed before starting normal climb.

    Maybe those 2 mistakes might have played role in the crash during first flight???

    Maybe the third reason for the crash is that settings in FSX.cfg is set to false in automixture in realism paragraph even though I did the job set proper automixture in Carvair???

    Apart from trying to figure out why I crashed in the first flight and unimpressive but completed second flight, there is problem of Carvair having inability to go above 160 kt speed.

    Is the speedometer gauge really in KNOTS or MIlES PER HOUR????

    Going to make third Carvair flight soon trying to recreate strange success of flight flown by Nagpaw who managed to achieve normal 190 kt cruising speed at full cargo load or is it 190 mph in gauge???

    ARRGGHHHHh

    Regards,

    Aharon

  12. #12
    Quote Originally Posted by Mike71 View Post
    LOTS of planes have ASI's in mph. I hate it, but it is reality.
    Me too I think speedometer gauge should be in knots and mach

    Regards,

    Aharon

  13. #13
    Quote Originally Posted by MrZippy View Post
    Aharon,

    Shortly after wheels up, be sure to get your Prop RPMs down into the green zone. If you don't, this may happen....as shown with the MJahn C-47 V2
    Famous Mr Zippy,

    I know what you mean and I always use 75 percent throttle power and 75 percent propeller throttle in Jahn DC-3/C-47 version THREE, not two but Flight Replicas does not have built in failure in the DC-4 package therefore it is not reason for crash in first flight. Besides, the crash just happened seconds after take off not during climb.

    Regards,

    Aharon

  14. #14
    Quote Originally Posted by Aharon View Post
    The two mistakes are that I should have set cowl flaps at 50 or 25 percent instead of 100 percent and that I started climb too soon after take off when I was supposed to take off and level off at 200 fpm after take off to gain plenty of speed before starting normal climb.

    Maybe those 2 mistakes might have played role in the crash during first flight???

    Maybe the third reason for the crash is that settings in FSX.cfg is set to false in automixture in realism paragraph even though I did the job set proper automixture in Carvair???
    Normally the cowl flaps would make a difference, as they create quite a bit of drag. But after some further research, it appears that the FR DC-4/Carvair flight models don't account for cowl flap drag. So that probably didn't make a difference on your failed flights. Climbing before you've gained sufficient airspeed certainly could have, especially if you were using the incorrect airspeed scale.

    I use the automixture with the FR DC-4 and Carvair just to make certain I'm getting the appropriate power. I know it's not perfect, but there's really no other way to adequately lean the engines manually.


    Quote Originally Posted by Aharon View Post
    Is the speedometer gauge really in KNOTS or MIlES PER HOUR????

    Going to make third Carvair flight soon trying to recreate strange success of flight flown by Nagpaw who managed to achieve normal 190 kt cruising speed at full cargo load or is it 190 mph in gauge???

    ARRGGHHHHh
    Yup, it's in miles per hour. If you press <SHIFT+Z> to bring the information bar up at the top of the screen you can read the airspeed in knots. Fly with both for little while and you'll be able to easily figure out the appropriate airspeeds in miles per hour by comparing the two indications.

    Also, I'd recommend using the published power settings. For each phase of flight, you'll have a range of manifold pressures and RPM to use. The documentation includes some general power settings, but you'll find exact settings in the outstanding flight planning charts included with the package. They're in your "SimObjects/Airplanes/Douglas C-54B/2. PERFORMANCE CHARTS folder. The cruise charts are titled, for example, "Cruise 50-45." The two numbers indicate the aircraft weight in thousands of pounds (i.e. 50,000 to 45,000 pounds). Make certain you're using the correct chart for your weight. There's a note at the bottom of each chart on converting the numbers for use with the Carvair.

    Also note that the charts give airspeed in TRUE airspeed. When you read a book or website about airplane performance specifications, the cruise speeds given are almost always TRUE airspeed, not INDICATED. As a rough guide, for any given indicated airspeed, true airspeed increases by about 2% per one thousand feet of altitude gain. If you're not familiar, here's a quick and dirty way to find your true airspeed, in this example for an indicated airspeed of 160 knots at 7,000 feet...

    1) Note the indicated airspeed in KNOTS from the <SHIFT+Z> data block at the top of your screen (160)

    2) Multiply that speed by 0.02 (160 x 0.02 = 3.2)

    3) Multiply the result by your altitude in thousands of feet (3.2 x 7 = 22.4)

    4) Add the result to your indicated airspeed in knots (160 + 22.4 = 182.4 knots)

    5) The result is your true airspeed in KNOTS.

    6) <OPTIONAL> Divide by 0.86 to find your true airspeed in MILES PER HOUR (182.4 / 0.86 = 212 mph)

    There's a formula to convert the other way, but I won't muddy the waters just yet

    Whoops! I have to head to work for a few days, but I'll try and check your progress along the way. I know it's frustrating, but I think you're getting there!
    America never stopped being great.

  15. #15
    And while you're pondering all that check out
    international standard atmosphere, and realise that all gauges are baseline calibrated to it so any variation above or below isa will affect what is seen on gauge,

    Ttfn

    Pete

  16. #16
    Charter Member 2017 srgalahad's Avatar
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    Alas,f you lift off at barely stall speed, already producing max. power, it is unlikely that you will get above stall. Given that our controllers are rarely precise enough to make 1* pitch changes all you will get is a period of mushing along on the edge of the stall until you encounter a solid object. Always. This isn't just a FS thing either as accident databases will prove. Moving on...

    Following published tables is always a good idea, but yes, the right units must be applied. Knowing the conversions is essential and takes time and practice.
    As far as manual leaning is concerned, it's difficult if the model does not have things like EGT gauges. However, there is a simple solution: Herve Sors' Advanced Flight Simulator Data (AFSD) is a small program that displays all the data from the sim (by category). Run it, check the "Fuel" table, looking at F/A Ratio as you approach max. power on takeoff (or during runup, if you do one of those) and adjust the mixture. Then check it every couple of thousand feet in the climb and adjust, tweak at cruise and repeat on descent. The Target is .08333 which is what FSX thinks is optimum.
    AFSD's tables also show precise, real-time IAS + TAS + CAS and, if selected, will give an updated stall speed as fuel/weight is lost. I use it constantly when testing new models and in those odd situations like max. range flights to squeeze every mile out of the fuel.

    As far as getting a sim aircraft to match "book" or brochure or Wiki data, I always work on the premise that it (FSX) is a$49 bit of software, trying to read/display another $49 bit of software, both of which were written on a budget and within time constraints: Close is good - but your mileage may vary.

    "To some the sky is the limit. To others it is home" anon.
    “Anyone who has never made a mistake has never tried anything new.” -Albert Einstein


  17. #17
    Thanks all again for kind explanations and for useful hyperlinks

    Nagpaw,

    I had one failed Carvair flight, NOT failed flights The second was success BUT totally unimpressive to me.

    Will make third Carvair flight soon and will let all of you know about the results. I suspect that I had been flying too many DC-4 flights enough to fail to realize that Carvair does NOT necessarily have same performances as DC-4/C-54 especially when the former has 747 style hump! That might account for my failed first Carvair flight thinking that Carvair should have same performance as DC4/C-54

    Regards,

    Aharon

  18. #18
    OKAY OKAY OKAY

    With self corrections such as setting cowl flaps at 50 percent instead of 100 and level off immediately at 200 fpm to build up speed after take off instead of immediate climb have solved the problem and everything was successful using 50 percent fuel load, 10,000 lb payload, and 600 lb, not 900 lb crew load.

    HOWEVER, it fails to solve one problem which is SPEED.

    Carvair will not go above 155 kt (I added my own gauge in kt reading) or 180 mph in Carvair cockpit speedometer gauge reading. Carvair is supposed to have top speed of 220 kt and cruising speed of 190 kt. Because of extremely too slow speed, I could not reach my desired 9,000 ft and had to settle for 5,000 ft cruising altitude because climb was very very painful slow at much lower 130 kt speed.

    What can I do to correct the speed problem?? I tried to reduce propeller control throttle to 73 percent to make sure the rpm gauge stays on top of green just below red to test my theory that this will help increase speed if engines are more happy but that reduced cruising speed from 155kt to 150 kt.

    Regards,

    Aharon

  19. #19
    Is 220 KIAS a never exceed or max operating speed? Vne is typically achieved in a descent, not achievable in level flight at full max continuous power. Vno is often a stability degradation / gust factor issue. I will see what I can find out.

    One way to cheat is modify the aircraft.cfg file: the line power_scalar = 1 in 10% increments to see what happens

  20. #20
    Hi all, this thread just made me curious, been flying the JBK C-54 a lot lately. lets see if my numbers help.

    The aircraft was loaded with 800 + 7400 + 800 for a total 9000 lb
    for the flight Southend - Strasburg, I loaded 965 gals of fuel (flight + 1 hour reserve), that gave me a take off weight of 57969lb
    I use RealEngine 1.4 to set up limits and monitor the engines and importantly to maintain "auto rich" (8.5%) and "auto lean" (7%) mixture.
    Weather was real +6C, wind 049/10 on take off and QNH 29.68

    For the take off, flaps 10 and full throttle (50", 2700 RPM) was used up to 200ft then wheels up and reduction to 38", 2500 RPM and flaps up. like that she would happily climb at 140/150 KIAS at 500 fpm, temps in the green with 30% cowl flaps to selected cruise altitude of 8000 ft.

    Once at 8000 feet, I left everything as per climb and let accelerate, it finished at 197 KIAS, that given the conditions were 220 KTAS, then reduction to 31", 2050 RPM and "auto lean" which gave 156 KIAS, equivalent to 175 KTAS and all temperatures in the green.

    Temperature , pression and weather were obviously changing along the way but the performance was stable.

    The only thing I tweaked in this plane is reducing the cruise lift scalar to 0.9 as it had a tendency to fly nose down from 160 KIAS on
    I got the numbers to fly it from a real manual downloaded from internet.

    Hope it helps
    Born to Fly

  21. #21
    Quote Originally Posted by Mike71 View Post
    Is 220 KIAS a never exceed or max operating speed?
    Good morning Mike,

    Please please please remember I am NOT NOT kind of crazy flight simmer who likes to fly at top speed in most unrealistic manner. According to various info, 220 kt is max operating speed and 180-190 kt is cruising speed at 10,000 ft.

    I always believe in recreation of real world realistic flights in most realism manner.

    You got to remember there are TWO kinds of realistic cruising speeds for DC-4s, C-54s, and Carvairs. The cruising speed for those planes when brand new and in regular daily service during 1950s are MUCH higher than cruising speeds of Buffalo or any airline DC-4s/C-54s at present 21st century era. Buffalo or any airline would fly those planes at much lower speeds in 21st century than what planes would normally fly in era 1950s. In other words, flying at 155kt would be normal cruising speed for Buffalo Airways DC-4s/C-54s in 21st century but NOT normal for American Airlines or Pan Am DC-4 which could do at higher but normal cruising speed of 180-190kt in 1950s.

    So I am setting speed BASED on which year any of those aircrafts flew in the past to recreate most realistic realism of historic flights so I would be flying Carvairs in era 1960s at normal cruising speed of 180-190 kt which is the speed I am unable to recreate in most realistic manner. If it was Buffalo Airways DC-4/C-54, that would be perfect slower speed at 155kt (I think Buffalo Airways picks 145kt) and I would not be asking around here for help to solve the problem.


    Quote Originally Posted by Mike71 View Post
    I will see what I can find out.
    Would appreciate that


    Quote Originally Posted by Mike71 View Post
    One way to cheat is modify the aircraft.cfg file: the line power_scalar = 1 in 10% increments to see what happens
    I am definitely not going to tinker with aircraft.cfg or otherwise I would invalidate warranty and lose tech support from Flight Replicas. The only exception is me adding to the DC-4 package my speedometer gauge in kt reading because I always use kt, not mph when flying.

    Regards,

    Aharon

  22. #22
    Quote Originally Posted by Ascua View Post
    Hi all, this thread just made me curious, been flying the JBK C-54 a lot lately. I got the numbers to fly it from a real manual downloaded from internet.
    Cool and thanks for doing test flight. However I have feeling that Carvairs have FAR MUCH different flying performances and dynamics than DC-4s/C-54 due to the fact that the former has massive hump and the latter does not have. I think the hump can affect the air flow. That is unless foremost aviation experts tell me it is NOT true that massive hump on Carvair can affect air flow.

    And care to tell us where you found real manual from the internet, please?

    Regards,

    Aharon

  23. #23
    Certainly, there you go, it is for a C-54G

    https://ww2aircraft.net/forum/attach...ns-pdf.610177/

    Also, but not so informative

    https://www.filefactory.com/file/42t..._DC-4%20OM.pdf

    Saludos
    Born to Fly

  24. #24
    Thanks, Asgua for the cool hyperlinks!!

    After finishing three Flight Replicas Carvair flights thanks to great help, corrections, and suggestions by everybody here at SOH forums, I am NOW ready to make first flight with Flight Replicas DC-4 to see what flying dynamics and speed look like!!

    The first DC-4 flight will be loaded with 35 percent fuel, 600 lb crew, and heavier 12,000 lb of cargo load to recreate historic flight between CYZF and CYHY by Buffalo Airways DC-4 doing emergency last minute Christmas gifts and food load supply from CYZF to CYHY. I hope to be able to reach 9,000 ft cruising altitude!

    Regards,

    Aharon

  25. #25
    Aharon,

    I'm back! Reading some more into the thread, I want to make certain that we're talking about the same numbers. Most of the specifications I find for the Carvair say she cruises at about 180 knots at 10,000 feet. That 180 knots is very likely True Airspeed (TAS), not Indicated (IAS). At 10,000 feet, a TAS of 180 knots would be about 150 knots IAS, or 174 miles per hour on the airspeed gauge. Is that the speed you're getting, and how much power is required to hold that?
    America never stopped being great.

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