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weight and performance calculations for the McDonnel Douglas DC-9-15
KLM DC-9-15 PH-DNA c/n 45718/17
McDonnel Douglas DC-9-15
role : short-range regional jet airliner
importance : ****
first flight : DC-9-10 : 25 February 1965 operational : DC-9-11 December 1965
(Delta), DC-9-15 in Europe KLM : April 1966
country : United States of America
ICAO aircraft type designator : DC91
production : srs-10 : 137 (-11 : 3) (-12 : 1) > later converted to -14. (-10C : 24) (total DC-9 :
976) at Long Beach
general information :
At the end of the fifties, the French came up with the Caravelle and this soon became a
resounding success. It supplanted piston airplanes and the new turboprops from European routes and it was even sold in America (United). The English answered with the more economical BAC 1-11 and in America Douglas started working on the design of the DC-9, initially equipped with four turbojets and more or less a scaled-down DC-8. However, there was little interest in this. Douglas began designing a new DC-9 with two tail motors. However, it had few funds at that time because the development costs of the DC-8 had not yet been recouped. In the design, a lot of attention was paid to the comfort of the passengers, lower operating costs per mile than the types in use at the time for the short distance, and the passenger capacity had to be precisely tailored. Simplicity and reliability of the aircraft and the systems were very important so that little maintenance would be required. In April 1963 the final design was ready and the decision was made to build the aircraft definitively, although no orders had been placed at that time. The development costs were estimated at 100 million USD and the unit price was set at 3.1 million USD. Due to its short range, it had to be designed for a large number of take-offs and landings.
Delta Airlines DC-9-14 inauguration .
Subcontractors were appointed for the construction, for example, De Havilland Canada built the wing and tailplane and the Rohr Corporation built the engine nacelles and thrust reversers. These subcontractors took care of part of the development costs and in this way there was sufficient capital for the development of the DC-9. At the end of April 1963, Delta was the first to place an order for 15 DC-9s. But sales were difficult because world aviation was in a deep economic crisis at that time due to the hasty switch to the jet aircraft and the resulting overcapacity. It was not until the late sixties that the airlines recovered from the dip.
The first engines used for the type -11 were the JT8D-5 turbofans, derived from the JT8D-1, but which instead of 62.3 KN of thrust, delivered 53.4 KN of thrust because the rpm and operating temperature were reduced. As a result, the engine required less maintenance. The late -15 model used the more powerful JT8D-7 engine delivering 62.3 KN.
The wing was given an sweepback of only 24°, which gave good properties at lower speed and still allowed for a high cruising speed.
The wing had double-slotted flaps.
When choosing for the T-tail, the dangers of "deep-stall" were carefully considered. If the main wing becomes stalled, there is a chance that the T-tail stabilizer will come into the wake of the wing and the nose will not automatically drop, as is usual with a normal tail, but will tend to go up even more. It was solved by the "stick-shaker", when there is a threat of a stall situation, the control stick will shake violently and all kinds of horns will sound. If the pilot does not respond, a robot will automatically push the control stick forward with great force.
To keep the airplane simple, the systems (climate, de-icing, hydraulics, fuel and electricity) were built from as few parts as possible and parts were used that were already on the market and had proven their reliability. The hydraulic system needed 218 bar during take-off and landing, but during the cruising flight 109 bar was sufficient for the operation of the rudders. The crew was able to reduce the pressure during the flight, which significantly extended the life of the system. The cockpit of the DC-9 became the same as that of the DC-8. On February 25, 1965, the prototype made its first flight, a month ahead of schedule.
The flight crew consisted of only two men.
Delta Airlines DC-9-14 with passengers climbing the built-in airstair .
For quick handling at the airport, the aircraft was equipped with an auxiliary power unit (APU) in the tail and it had a built-in airstair for the forward passenger entrance.
A plus was also the relatively large cargo space under the cabin floor. The Max . landing weight amounted to 95% of the MTOW, which could save the weight of the fuel dump system, but the landing gear had to be extra strong. But later this was an advantage when the extended versions appeared.
The DC-9-10 was delivered in four different configurations, three passenger layouts, with max. 90 passengers and a combi version.
The initial DC-9 versions was the -11 with 54.5 KN JT8D-5 engines which entered
service December 1965 with Delta Airlines. Only 3 built of this version. Production
switched quickly to the higher powered -14 (38900 kg MTOW) and -15 (41100 kg
MTOW). Both with increased fuel capacity.
Despite the competition from the BAC 1-11 and later the Boeing 737, the DC-9 was a great success. In April 1967 a total of 441 aircraft had been ordered. But Douglas' sales team sold many more aircraft (including the DC-8) than the production line could handle. Production had to be increased considerably in order to be able to deliver on time. But the DC-8 and DC-9 were built in a large number of different versions that were also adapted to the special individual wishes of the customer. Both aircraft were built on the same production line and all the different versions were built side by side (so one version did not succeed the other version on the production line) and this made it difficult to increase production. In addition, the Vietnam War had erupted in all its intensity and war production was given priority by the subcontractors and it became increasingly difficult to obtain parts.
KLM DC-9-15 PH-DNE c/n 45722/55 at Dusseldorf apt (DUS), 1967 .
To increase production, a large investment was necessary, but Douglas did not have the money for this. At the end of 1966, Douglas suddenly suffered a considerable loss and bankruptcy was in the air. Airlines began to file substantial claims for the ever-delayed delivery dates. McDonnel, builder of the very successful F-4 Phantom II, was well off and wanted to enter the civilian market in order to no longer be solely dependent on defence orders. On April 28, 1967, the merger of the two companies was a fact.
The KLM ordered 6 DC-9-15’ s for 90 million guilders including pare parts and flight simulator. All aircraft were delivered in 1966. On March 26, 1966, the very first DC-9 arrived at Schiphol, more than two months late. KLM started to operated the DC-9 in April 1965 as first airline in Europe.
The DC-9 had a Sperry Flight Director with which, in combination with the auto-pilot, category II landings could be carried out.
The crew had to keep the engine power, if possible, below 54.5 KN because of the maintenance costs. The MTBO of the engines was estimated at 2500 hours.
The DC-15 of the KLM did not have the optional exit in the tail, it only had a door for the passengers at the front of the fuselage. The on-board kitchen was a KLM design and had to be placed directly behind the cockpit according to Douglas' instructions, at the expense of two rows of seats in the quietest part of the cabin. As a result, the seats had to be placed as far back as possible in the fuselage. These rear seats became notorious among passengers for the noise of the engines despite extra soundproofing. But soon passengers and crew were convinced that the DC-9 was an excellent aircraft. It saved a lot of time on the European routes and the flight attendants were no longer able to serve a hot meal due to the short flight time. KLM then decided to serve only cold dishes on all short and medium-haul flights.
On April 25, 1966, KLM opened the first DC-9 scheduled service in Europe. The PH-DNA "Amsterdam" flew Amsterdam – Geneva – Nice.
KLM DC-9-15 PH-DNC c/n 45720/27 at Zurich apt (ZRH), August 1980 .
The PH-DNC "Luxembourg" was by far the longest in service with KLM, from May 1966 to February 1989, almost 23 years. It made 41090 flight hours and 41119 take-offs (avg. 5.43 flight hours per day). Converted, this comes to 1806 flight hours per year, which is a lot (22%) less than the average of other airlines: 2330 flight hours per year.
primary users : KLM (6), West Coast Airlines, TWA (20), Ozark Airlines (6), Delta
Airlines (14), Finnair, Aeromexico, AVENSA (2), Texas int’l airlines (7), Eastern Air
Lines (15), Republic airlines, Continental (19) , Northwest airlines, Swissair (5), Air
Canada (6), British Midland
KLM registrations : PH-DNA “Amsterdam”, PH-DNB “Brussel”, PH-DNC
“Luxemburg”, PH-DND “Hamburg”, PH-DNE “Rome”, PH-DNF “Parijs”
Accommodation :
flight crew : 2 cabin crew : 3
passengers : seating for 68 in two class : 8 first class and 60 coach class seats ( 34 -in
pitch) high density seating for max 90 passengers (equal to exit limit)
engine : 2 Pratt & Whitney JT8D-7 turbofan engines of 62.27 [KN] (13999 [lbf])
Measured chord at root : 4.92m at tip : 1.48m , geometric tail angle : 13°.
dimensions :
wingspan : 27.25 [m], length overall: 31.82 [m], length of fuselage : 28.07 [m] height :
8.35 [m] wing area gross : 86.77 [m^2] fuselage exterior width : 3.34 [m]
weights :
manufacturer’s weight empty : 21660 [kg]
operating empty weight : 22300 [kg] max. structural payload : 11266 [kg]
Zero Fuel weight (ZFW) : 33566 [kg] max. landing weight (MLW) : 37059 [kg]
max. take-off weight : 41141 [kg] weight usable fuel : 10974 [kg] (13979 [litres])
performance :
Max. operating Mach number (Mmo) : 0.812 [Mach] (903 [km/hr]) at 7620 [m]
critical Mach speed : 0.77 [Mach]
max. cruising speed : 871 [km/hr] (Mach 0.800 ) at 9150 [m] (31 [%] power)
economic cruising speed : 830 [km/hr] (Mach 0.76 ) at 9150 [m]
service ceiling : 10000 [m]
range with max fuel and MTOW : 2760 [km] (ATA domestic fuel reserves - 370.0 [km]
alternate)
description :
*Cantilever low-wing monoplane with retractable landing gear with nose wheel
engines attached to the tail, landing gear attached to the wings, fuel tanks in the
wings
*Wings : aluminium alloy fail safe wing structure with double slotted trailing edge
flaps with no leading edge flaps ,with spoilers airfoil : NACA
average thickness/chord ratio : 11.6 [%], sweep angle 3/4 chord: 24.0 [°]
incidence at root : 1.00 [°], dihedral : 6.0 [°]
Delta Airlines commercial showing DC-9-14 N3303L c/n 45698 .
*Tail Unit: Cantilever all-metal structure with tailplane mounted at tip of fin
*Fuselage : Pressurized conventional all-metal fail safe structure with double-bubble
cross section
calculation : *1* (dimensions) :
measured wing chord at root: 4.92 [m]
measured wing chord at tip : 1.48 [m]
measured geometric tail-angle : 13.0 [° ]
taper ratio : 0.301 [ ]
mean wing chord : 3.18 [m]
wing aspect ratio : 8.56 []
Oswald factor (e): 0.692 []
seize (span*length*height) : 7240 [m^3]
calculation : *2* (fuel consumption) :
oil consumption : 4.2 [kg/hr]
fuel consumption (econ. cruise speed) : 2909.9 [kg/hr] (3706.9 [litre/hr]) at 29 [%]
power
fuel burn per seat per hour (average seating) : 46.92 [litre], sfc : 80.6 [kg/KN/h]
calculation : *3* (weight) :
weight engine(s) dry : 3000.0 [kg] = 24.09 [kg/KN]
weight 23.7 litre oil tank : 2.02 [kg]
oil tank filled with 0.8 litre oil : 0.7 [kg]
oil in engine 1.5 litre oil : 1.4 [kg]
weight all fuel lines and pumps containing 57 litres fuel : 28.3 [kg]
weight engine cowling : 323.8 [kg]
weight thrust reversers : 186.8 [kg]
total weight propulsion system : 3543 [kg](8.6 [%])
***************************************************************
Accommodation cabin facilities :
typical 2-class cabin layout for 68 passengers : economy : pitch : 86.4 [cm] 34.0 [-in]
( 3+2 ) seating in 14.0 rows, first class pitch : 96.5 [cm] 38.0 [-in] at 4 -abreast
weight passenger seats (width 52.6 [cm]) : 392.3 [kg]
weight cabin crew seats : 15.0 [kg]
weight flight crew seats : 42.0 [kg]
high density seating passengers : 90 [pax] at mainly 5 -abreast seating in 18.6 rows,
pitch 73.7 [cm] 29.0 [-in]
pax density, normal seating : 0.785 [m2/pax], high density seating : 0.593 [m2/pax]
weight 2 lavatories : 57.3 [kg]
weight 2 galleys : 63.6 [kg]
weight overhead stowage for hand luggage (total : 4.6 [m3] = 96 55x35x25cm carry-on
trolleys) : 71.8 [kg]
weight 1 wardrobe closets : 16.0 [kg]
weight 30 windows (41 x 28 cm) made of acrylic glass : 127.5 [kg]
weight 1 (1.83 x 0.86 [m]) main entry doors : 37.8 [kg]
weight 1 (1.22 x 0.69 [m]) crew/service doors : 20.2 [kg]
weight built-in airstair for the front passenger door : 83.5 [kg]
weight 2 (main door size : 1.35 x 1.27 [m]) freight doors (belly) : 89.3 [kg]*
total usable belly baggage/cargo hold volume : 18.4 [m3]
passenger compartment volume : 68 [m3]
cabin volume (usable), excluding flight deck : 98 [m3]
passenger cabin max width : 3.14 [m] cabin length : 16.99 [m] max cabin height : 2.06
[m] floor area : 47.4 [m2], cabin width at floor : 2.87 [m]
11.7 [%] of cabin floor area is occupied by toilets & galleys, the same at high density
seating
weight cabin facilities : 932.7 [kg]
safety facilities :
weight 2 type III over wing emergency exits (0.51 x 0.91 [m]): 24.1 [kg]
evacuation time with 90 passengers : 54 [sec]
weight 2 hand fire extinguisher : 7 [kg]
central aisle : 0.51 [m] wide
weight cockpit voice recorder (CVR) and flight data recorder (FDR): 20.0 [kg]
weight oxygen masks & oxygen generators (deploy cabin alt.>4267m): 44.2 [kg]
weight emergency flare installation : 10 [kg]
weight 2 emergency evacuation slides : 51.6 [kg]
weight safety equipment & facilities : 241 [kg]
The double-bubble fuselage shape gives more under-floor belly cargo space.
Trim to trim width : 3.14 m .
fuselage construction :
fuselage aluminium frame : 4117 [kg]
floor loading (payload/m2): 238 [kg/m2]
weight rear pressure bulkhead : 151.6 [kg]
fuselage covering ( 197.1 [m2] duraluminium 3.29 [mm]) : 1704.3 [kg]
weight paint fuselage : 41.4 [kg]
weight aluminium floor beams : 170.7 [kg]
weight cabin furbishing : 354.4 [kg]
weight cabin floor : 632.2 [kg]
weight (sound proof) isolation : 194.4 [kg] TO-noise level : 116.0 [EPNdB]
weight empty 55 [litre] potable water tanks : 4.9 [kg]
weight empty waste tank : 2.5 [kg]
weight engine mounts : 62 [kg]
weight fuselage structure : 7436.0 [kg]
Avionics :
weight HF/VHF radio and Selcal : 8.0 [kg]
weight Marconi Doppler and Bendix transponder : 7.0 [kg]
weight weather radar : 25.0 [kg]
weight ARINC 550 Automatic Direction Finding (ADF) equipment : 8.0 [kg]
weight ARINC 521D Distance Measuring Equipment (DME) : 5.0 [kg]
Cockpit of Marshal service DC-9-15 N813TL c/n 45732
weight Instrument Landing System (ILS/VOR) : 5.0 [kg]
weight Sperry AD-200 flight director system with Sperry SP-50A auto-pilot : 25.0 [kg]
weight Cat II minima DH 30m RVR >=350m autoland system : 20.0 [kg]
weight artificial horizons, gyro-compass, radio altimeters : 7 [kg]
weight engine monitoring gauges & control switches : 14 [kg]
weight reserve ADI, ASI, alti-meter, compass, engine temp. and rpm indicators : 15
[kg]
weight avionics : 140.0 [kg]
Systems :
Air-conditioning and pressurization system maintains sea level conditions up to 5900
[m] and gives equivalent of 2250 [m] at 10700 [m]. pressure differential : 0.54 [bar]
(kg/cm2) pressurized fuselage volume : 109 [m3] cabin air refreshment time : 2.5
[min]
weight air-conditioning and pressurization system : 74 [kg]
weight Auxiliary Power Unit (APU) : 15.6 [kg]
weight lighting : 22.4 [kg]
weight 210 [bar] hydraulic system : 12.2 [kg]
weight engine-driven 40kVA electricity generators : 17.0 [kg]
weight 22Ah battery : 28.5 [kg]
weight controls : 13.0 [kg]
weight systems : 183.2 [kg]
total weight fuselage : 8933 [kg](21.7 [%])
***************************************************************
wing construction :
total weight aluminium ribs (107 ribs) : 1428 [kg]
weight 6 wing fuel tanks empty for total 13979 [litre] fuel : 210 [kg]
weight 56 [litre] vent surge tanks : 7 [kg]
weight wing covering (painted aluminium 3.17 [mm]) : 1486 [kg]
total weight aluminium spars : 1821 [kg]
weight wings : 4735 [kg]
weight wing/square meter : 54.57 [kg]
weight bleed air thermal leading-edge anti-icing : 30.0 [kg]
ALM – Dutch Antillean Airlines DC-9-15 PJ-DNC “Curacao” c/n 45721/44 .
weight two boundary-layer fences ( vortilons ) : 30.0 [kg]
weight ailerons (3.2 [m2]) : 87.2 [kg]
weight fin (7.3 [m2]) : 259.4 [kg]
weight rudder (3.4 [m2]) : 90.5 [kg]
weight tailplane (horizontal stabilizer) (20.2 [m2]): 608.1 [kg]
weight elevators (5.0 [m2]): 74.0 [kg]
weight paint wing & tail surfaces : 48.0 [kg]
weight trailing-edge double slotted flaps (18.0 [m2]) : 421.6 [kg]
weight spoilers (2.5 [m2]) : 39.6 [kg]
total weight wing construction : 6640 [kg] (29.8 [%])
*******************************************************************
landing gear :
tire pressure main wheels : 9.10 [Bar] (nitrogen), ply rating : 20 PR
tire speed limit : 364 [km/hr]
total tyre footprint : 0.18 [m2]
Runway LCN at MTOW (0.76m radius of rigidity) : 59 [ ]
Aircraft Classification Number (ACN), MTOW on rigid runway and medium subgrade
strength (B) : 25 [ ] good soft ground capabilities
wheel pressure : 9051.0 [kg]
wheel track 5.03 [m], wheelbase : 13.32 [m]
weight 4 Dunlop 40.0 x 14.0 main wheels (1016 [mm] by 356 [mm]) : 335.0 [kg]
weight 2 nose wheels : 83.7 [kg]
weight heavy-duty hydraulic disc brakes : 39.5 [kg]
weight Hydro-air flywheel detector type anti-skid units : 5.4 [kg]
weight oleo-pneumatic shock absorbers : 44.8 [kg]
weight wheel hydraulic operated retraction system : 492.1 [kg]
weight tailskid : 25 [kg]
weight undercarriage struts with axle 1410.5 [kg]
total weight landing gear : 2436.0 [kg] (5.9 [%]
*******************************************************************
Turkish Airlines DC-9-15 TC-JAA “Topkapi” c/n 47048/35 .
********************************************************************
calculated empty weight : 21551 [kg](52.4 [%])
aircraft equipment and service utensils :
weight oil for 3.8 hours flying : 18.9 [kg]
unusable fuel in engine and tanks 118.8 litre fuel : 93.3 [kg]
weight lifejackets : 30.6 [kg]
weight 1 life rafts : 42.5 [kg]
weight catering : 35.6 [kg]
weight water : 49.1 [kg]
weight crew : 405 [kg]
weight crew luggage, navigation chards, flight docs (NOTOC), manuals, miscellaneous
items : 74 [kg]
operational weight empty : 22300 [kg] (54.2 [%])
KLM DC-9-15 PH-DND “Hamburg” c/n 45721/44 .
********************************************************************
useful load breakdown :
weight 68 passengers : 5236 [kg]
weight luggage : 1088 [kg]
weight cargo : 4942 [kg] (cargo + luggage/m3 belly : 261.8 [kg/m3])
zero fuel weight (ZFW): 33566 [kg](81.6 [%])
weight fuel for landing (1.2 hours flying) : 3493 [kg]
max. landing weight (MLW): 37059 [kg](90.1 [%])
max. landing weight higher than max. fuel weight makes it possible to make
intermediate stops without refuelling and no fuel-dump system needed.
max. fuel weight : 33274 [kg] (80.9 [%])
payload with max fuel : 85 passengers + luggage 7867 [kg]
can be operated with high density seating with max.fuel for good economics
published maximum take-off weight : 41141 [kg] (100.0 [%])
Air Canada DC-9-14 CF-TLC c/n 45712 .
calculation : * 4 * (engine power) :
power loading (Take-off) : 330 [kg/KN]
power loading (Take-off) 1 PUF: 661 [kg/KN]
max. total take-off power : 124.5 [KN]
calculation : *5* (loads) :
manoeuvre load : 1.4 [g] at 9000 [m]
limit load : 2.5 [g] ultimate load : 3.8 [g] load factor : 2.3 [g]
design flight time : 0.85 [hours]
design cycles : 57800 sorties, design hours : 49130 [hours]
max. wing loading (MTOW & flaps retracted) : 474 [kg/m2]
wing stress (2 g) during operation : 162 [N/kg] at 2g emergency manoeuvre
Midway Airlines DC-9-15 high-density 83 seat 34-in coach-class cabin layout .
calculation : *6* (angles of attack) :
angle of attack zero lift : -1.72 ["]
max. angle of attack (stalling angle, clean) : 13.95 ["]
max. angle of attack (full flaps) : 13.84 ["]
Stick pusher stall warning for to high pitch up angle at lift-off
angle of attack at economic cruise speed : 2.08 ["]
calculation : *7* (lift & drag ratios) :
lift coefficient at angle of attack 0° : 0.15 [ ]
lift coefficient at max. speed : 0.26 [ ]
lift coefficient at max. angle of attack (clean): 1.36 [ ]
max. lift coefficient ( 50 [° ] flaps) : 1.58 [ ]
Saudi Arabian Airlines DC-9-15 HZ-AEA .
drag coefficient at max. speed : 0.0353 [ ]
drag coefficient at econ. cruise speed : 0.0342 [ ]
induced drag coefficient at econ. cruise speed : 0.0059 [ ]
drag coefficient (zero lift) : 0.0283 [ ]
lift/drag ratio at econ. speed : 7.24 [ ]
calculation : *8* (speeds) :
minimum control speed (Vmc): 263 [km/u] (141.8 [kt])
minimum unstick speed (Vmu) at TO angle 11.8 ° : 257 [km/u] (139 [kt])
take-off decision speed (V1) : 264 [km/u] (143 [kt])
take-off rotation speed (VR) : 276 [km/u] (149 [kt])
Aero California DC-9-15 XA-AGS c/n 45786/90
lift-off speed (VLOF) : 297 [km/u] (160 [kt]) at pitch angle : 8.2 [°]
take-off safety speed (V2) : 299 [km/u] (161 [kt])
flap retraction speed (V3) at 500m (OW loaded : 38231 [kg]): 287 [km/u] (155 [kt])
steady initial climb speed (V4) : 325 [km/u] (175 [kt])
climb speed (to FL150 with 63 [%] power) : 496 [km/hr] (268 [kt])
max. endurance speed (Vbe): 381 [km/u] min. fuel/hr : 2198 [kg/hr] at height : 2134 [m]
max. range speed (Vbr): 810 [km/u] (0.76 [mach]) min. fuel consumption : 3.13 [kg/km]
at cruise height : 10668 [m]
Eurocontrol diagram, V2 indicated as 115 kts, calculated 161 kts ! 115 kts seems to low .
max. cruising speed : 871 [km/hr] (470 [kt]) at 9150 [m] (power:33 [%])
max. operational speed (Mmo) : 903 [km/hr] (Mach 0.81 ) at 7620 [m] (power:42 [%])
airflow at cruise speed per engine : 90.5 [kg/s]
speed of thrust jet : 1698 [km/hr]
initial descent speed 10000 - 7315 [m]: Mach 0.75
descent speed 7315 - 3048 [m]: 537 [km/u] (290 [kt])
approach speed 3048 - 500 [m] (clean): 463 [km/u] (250 [kt])
minimum control speed (MCS) Vmca (clean): 274 [km/u] (148 [kt])
stalling speed clean at 500 [m] height at Max.Landing Weight : 37059 [kg]): 261 [km/u]
(141 [kt])
Aeromexico DC-9-15 XA-SOJ c/n 45785/64 “Oaxaca” on final approach .
final approach speed (landing speed) at sea-level with 50 [°] flaps VREF (max. landing
weight): 279 [km/u] (151 [kt])
ICAO Aircraft Approach Category (APC) : D
stalling speed at sea-level with 50 [°] flaps VSO (max. landing weight): 214 [km/u] (116
[kt]
stalling speed at sea-level with 50 [°] flaps VSO at 41141 [kg] AUW): 226 [km/u] (122
[kt]
rate of climb (max. continuous power) at sea-level ROC (loaded, 63 % power) : 896
[m/min]
rate of climb at sea-level ROC (loaded, 75 % power) : 1243 [m/min]
rate of climb at 1000 [m] with 1 engine out (PUF/MTOW, 63 % power on remaining
engines) : 71 [m/min]
KLM DC-9-15 PH-DNA “Amsterdam” c/n 45718/17, looking at the picture it is not yet finished and still being worked on at the plant in Long Beach, US.
rate of descent from FL240 to FL100 (7315m > 3048m): 701 [m/min] (2300 [ft/min])
rate of descent during approach with landing gear extended, with use of spoilers: 243
[m/min] (4.1 [m/s])
calculation : *9* (regarding various performances) :
low wheel pressure, can also take off from unpaved runways
take-off distance at sea-level gravel/packed earth field : 1830 [m]
Brake kinetic energy capacity : 1057 [KW]
Take-off field length, standard day, sea level, dry runway : 2000m .
FAR TO runway length (TOFL) requirement at TOW 41141 [kg] standard day at
SL (= ASDA) : 1945 [m] JT8D-7 engines
ICAO Aerodrome Reference Code : 3C
Take-off flap setting : 20 [° ]
FAR landing runway : standard day, sea level dry runway : 5000 ft > 1525m . Calculated distance 1729m , so 200m difference I cannot account for.
+++ FAA certification landing distance : +++
landing weight : 37059 [kg], TE flap setting : 50 [°]
runway condition : dry , landing over 50ft (15m) at threshold at sea-level
with use of thrust reversers, glideslope : 3.00 [°]
FAR landing field length ISA at SL, dry runway : 1729 [m] (5673 [ft])
FAR landing field length ISA at SL, wet runway: 1977 [m] (6487 [ft])
max. lift/drag ratio : 12.82 [ ]
climb to 5000 [m] with max payload : 5.16 [min]
climb to 10000 [m] with max payload : 15.89 [min]
descent time from 10000 [m] to 250 [m] : 24.33 [min]
max. ceiling fully loaded (mtow- 60 min.fuel): 38231 [kg] ) : 16800 [m]
ceiling limited by max. pressure differential 12850 [m]
max. theoretical ceiling (OWE + 60 min.fuel) : 18900 [m] with flying weight :25210 [kg]
calculation *10* (action radius & endurance) :
range with max. payload: 2125 [km] with 11266.0 [kg] max. useful load (69.0 [%] fuel)*
range with high density pax: 2979 [km] with 90 passengers (95.4 [%] fuel)*
range with typical two-class pax: 3176 [km] with 68 passengers (100.0 [%] fuel)*
Range with max payload : 710 NM = 1315 km
Range with max. fuel (13968 litres) : 1490 NM = 2760 km
Ferry range ( zero payload) : 1800 NM = 3330 km .
range with max.fuel and MTOW : 3130 [km] with 5 crew and 85 passengers and 0
[kg] cargo*
ferry range (calculated): 3366 [km] with 2 crew and zero payload (100.0 [%] fuel)*
max range theoretically with additional fuel tanks total 24419 [litre] fuel : 5680 [km]*
* calculated ranges without fuel reserves
Available Seat Kilometres (ASK) : 265527 [paskm]
useful load with range 1000km : 11266 [kg]
useful load with range 1000km : 90 passengers
production (theor.max load): 9813 [tonkm/hour]
production (useful load): 9813 [tonkm/hour]
production (passengers): 74555 [paskm/hour]
oil and fuel consumption per tonkm : 0.297 [kg]
calculation *11* (operating cost) :
fuel cost per hour at econ.speed (3707 [litre]):2224 [eur] (19 [pax-km/litre fuel])
fuel cost per seat 1000km flight (86 [pax] 2-class seating): 31.30 [eur/1000PK]
oil cost per hour: 17 [eur]
Delta stewardess Miss Carol Marie Koberlein standing next to the airlines first McDonnell Douglas DC-9-14 N3304L “Delta Prince” c/n 45699 at Hartsfield-Jackson Atlanta International Airport in October 1965.
Carol Koberlein served with Delta Airlines till she retired in May 2000 .
crew cost per hour : 600 [eur]
list price 2024 : 52 [mln USD]
average flying hours in 1 year : 2330 [hours] technical life : 21 [year]
real average service life : 22 [years]
depreciation : 22 [years] to 10% residual value
financing interest per flying hour : 502 [EUR]
write off per flying hour : 842 [EUR]
mean time between engine failure (MTBF) : 5724 [hr]
insufficient engine reliability for ETOPS flights
can continue fly on 1 engine, low risk for emergency landing for PUF
workhours per day : 12.02 [hr]
average flight hours till crash : 0.70 [mln hr] (301 service years)
safe flight hours till fatality : 19782 [hr] (8.5 service years)
reservation pax liability/flying hour : 6.51 [SDR*] (8.14 [eur])
insurance cost per hour : 346 [eur] insurance rate : 4.2 [%]
engine maintenance cost per hour : 487.2 [eur]
wing maintenance cost per hour : 224.6 [eur]
fuselage maintenance cost per hour : 545.73 [eur]
tire life (time till worn out) : 105 [cycles]
maintenance cost per hour (excluding engines): 1342 [eur]
direct operating cost per hour: 6368 [eur], DOC per km : 7.67 [eur]
DOC per seat 1000km flight (86 [pax] 2-class seating): 85.42 [eur/1000PK]
DOC per seat 1000km flight (high density seating): 81.24 [eur/1000PK]
DOC per kg cargo for a 1000km flight : 0.65 [eur/kg] (= DOC/tonkm)
passenger service charge (depart at Schiphol): 11.34 [eur]
security service charge (depart at Schiphol): 10.08 [eur]
airport take-off fee / passenger : 3.24 [eur/pax]
airport landing fee / passenger : 3.24 [eur/pax]
retour ticket price 1000km trip : 249.30 [eur/pax]
price retour ticket Schiphol-Barcelona : 296.28 [eur/pax]
“Good-old” Ameristar DC-9-15RC N785TW c/n 47015/156 at Everett – Paine Field (PAE) October 2022. Delivered in 1967, in April 2025 the aircraft was still in service, when it got damaged while refuelling at Austin-Bergstrom apt, Texas .
10 fatal accidents with a total of 355 fatalities > see the accident file
Literature :
Jane s all the world aircraft 1964-65 page 213,
Jane s all the world aircraft 1970-71 page 398,399,400
KIJK straalverkeersvliegtuigen page 66,67,68
McDonnell Douglas DC-9 - Wikipedia
https://contentzone.eurocontrol.int/aircraftperformance/default.aspx?
https://www.boeing.com/search/results.html?q=airplane+characteristics
Verkeersvliegtuigen Moussault page 71, 141
Verkeersvliegtuigen B. Van der Klaauw page 38
KLM gegevens page 12,13
Luchtvaart dec’89 page 353 – 359
Amerikaanse vliegtuigbouwers page 68
The Flier’s handbook page 104
Onze burgervloot page 28
Verkehrsflugzeuge page 65
Carol Marie Koberlein | This Day in Aviation
confidence rating regarding source data : medium - all information is only available from news, social media or unofficial sources
DISCLAIMER Above calculations are based on published data, they must be
regarded as indication not as facts.
Calculated performance and weight may not correspond with actual weights
and performances and are assumptions for which no responsibility can be taken.
Calculations are as accurate as possible, they can be fine-tuned when more data
is available, you are welcome to give suggestions and additional information
so we can improve our program. For copyright on drawings/photographs/
content please mail to below mail address
(c) B van der Zalm 08 May 2026 contact : info.aircraftinvestigation@gmail.com ac jetpax 2020.py python 3.7.4
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