<?xml version="1.0" ?> 
<!--

For Flightgear 2.0 or later. Do not use for earlier versions.

  File:     WrightCyclone-972TC18DA3.xml
  Author:   Ron Jensn - Modified YAKKO 04-12-2010
  Date:     14 Feb 2010
  Version:  2.0

  Inputs:
    name:           WrightCyclone-972TC18DA3
    type:           piston
    power:          3250 hp


  References (for older 975C18CB1 model) :
  ==========
  - http://www.hars.com.au/fleet/constellation/facts.html :
  (VH-EAG : 1049-F, C-121C).

  445 l/h (118 gph) per engine : 24790 l, 3450 NM, 16.5 h maximum.
  
  - http://www.superconstellation.org/ :
  (N73544 : 1049F, C-121C).

  450 l/h (120 US gal/h) per engine : 6550 US gal, 3500 NM, 14 h without reserve.

  Note that 1 US gal = 3.75 l.

  - http://www.airliners.net/discussions/general_aviation/read.main/1738757/4/ :

  Max payload : 1049 1890 NM, 1049C 2510 NM.
  Max fuel : 1049C : 4760 NM.

  - http://www.airweb.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/MainFrame?OpenFrameSet
  (FAA certificate, 6a5 - 14 may 1952) :

   Tanks 2 and 3 (inboard) : 790 gal each, 9480 lb.
         1 and 4 (middle) : 1555 gal each, 18660 lb.
         2a and 3a (outboard) : 565 gal each, 6780 lb.
         5 (center section) : 730 gal, 4380 lb.

   A total of 6550 US gal = 24563 l : note that is 1 US gal = 6 lb !
   This content is the same from model 1049-54 to 1049D-55 : from 1049G-82, there are additional tanks at wing tip. 

   - http://www.airweb.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/MainFrame?OpenFrameSet
   (FAA certificate, E-270 - 28 december 1983) :

   Displacement : 3350 cu. in.

   ===== YAKKO MODIFICATION NOTES =====

   BSFC value tweaked to 0.305 to bring torque pressue and manifold pressures
   near alignment with known values.

   Known values taken from reference sheet found on the 1049H engineer's
   desk of operational aircraft at Airline History Museum, Kansas City:

   TAXI: Pitch set to max rpm/fine pitch, 1200 RPM.

   TAKEOFF: 2 minutes maximum at this setting
            MAP 51 inches, 2900 RPM, 216 BMEP
            (216 seems low here, cannot get FGFS to
             yield a value that low at these settings 
             without throwing all other values off).

   MAX EXCEPT TAKE OFF: 44 inches MAP, 2600 RPM 216 BMEP

   MAX CLIMB: MAP up to 40 inches, 2500 RPM, 200 BMEP

   STD CLIMB: MAP up to 38 inches, 2400 RPM, 185 BMEP

   CRUISE: MAP up to 41 inches, 2000 RPM, 170 BMEP
           585 punds/hour fuel flow

   LANDING: 2400 RPM (other values not known yet)

   ===== END YAKKO MODIFICATION NOTES =====

--> 
<piston_engine name="Wright Cyclone 972TC18DA3">

<!-- 
     - estimation of the 1049 range : 3580 NM = 4760 * 1890 / 2510.
     Which matches VH-EAG and N73544 with both the same content in US gal.

     - max speed is 220 kt at 20000 ft (cruise), 197 kt at 25000 ft (ceiling) : that is an average of 209 kt.
Ron:  These are apparently Indicated Air Speeds, the average is meaningless?
     Let's take 319 kt as average ground speed (tail wind 20 kt) : range is 3580 NM / 319 kt = 11 hours.

     For our model 1049-54, with 6550 US gallons, the consumption must be 6550 / 11 hours = 595 US gallons / hour,
     or 149 US gallons / hour per engine.
Ron: Model is set to give 2000 hp at 149 gph.
     For westerly front wind 10 kt (optimistic), average ground speed is 289 kt (optimistic), or 3580 / 289 = 12 h.
     And it can cross the Atlantic from the east (KJFK-EHAM 3156 NM direct), only with refueling at Gander or Shannon.
-->

   <minmp unit="INHG">  6.0 </minmp>
   <maxmp unit="INHG"> 56.5 </maxmp>
   <displacement unit="IN3"> 3350.00 </displacement>
   <bsfc> 0.305 </bsfc>
   <volumetric-efficiency> 0.5 </volumetric-efficiency>
   <maxhp>    3250.00 </maxhp>
   <cycles>      4.0 </cycles>
   <bore unit="IN"> 6.125  </bore>
   <stroke unit="IN"> 6.312 </stroke>
   <cylinders> 18 </cylinders>
   <cylinder-head-mass> 25.0 </cylinder-head-mass>
   <compression-ratio> 6.7 </compression-ratio>
   <sparkfaildrop> 0.9 </sparkfaildrop>
   <idlerpm>   500.0 </idlerpm>
   <maxrpm>       2900.0 </maxrpm>
   <maxthrottle> 1.0 </maxthrottle>
   <minthrottle> 0.1 </minthrottle>
  <boostmanual>      1 </boostmanual>
  <numboostspeeds>   2 </numboostspeeds>
  <boostoverride>    0 </boostoverride>
  <takeoffboost>     0</takeoffboost> <!-- takeoff boost not used because it works poorly. -->

  <ratedboost1 unit="INHG"> 28.0 </ratedboost1>
  <ratedpower1> 3250 </ratedpower1>
  <ratedrpm1>   2900 </ratedrpm1>
  <ratedaltitude1> 0 </ratedaltitude1>

  <ratedboost2 unit="INHG"> 18.5 </ratedboost2>
  <ratedpower2> 2400 </ratedpower2>
  <ratedrpm2>   2600 </ratedrpm2>
  <ratedaltitude2> 10800 </ratedaltitude2>

</piston_engine>
