Aircraft investigation >>>>>>> HOME PAGE

Afbeeldingsresultaat voor Sopwith Pup

Sopwith type 9901 “Pup”

role : fighter

first flight : February 1916 operational : October 1916

country : United-Kingdom

design : Herbert Smith

production : 1770 aircraft

general information :

important aircraft WOI. The Sopwith “Pup” was easy to fly, was manoeuvrable and

had good flight characteristics. It was simple of construction and was very strong. It

was an excellent fighter plane and both the RNAS and the RFC flew with it. It was

superior to the German fighters of the time, including the Albatros D. III. Due to its

short take-off run it was also well suited for use on aircraft carriers. On 2 August

1917, Sqn. Cdr. Dunning performed the first deck landing in history. He put his Pup

on the deck of the H.M.S. Furious at sea. Due to its low landing speed the seaman

could bring it to a stop by hand.

After his service at the front, the Pup was used as an advanced trainer for a long time, for which it was perfectly suitable due to its good flying characteristics. In the Pup, the pupil could test how it was to control a real fighter plane.

Military load 80 pounds = 36 kg (1 MG, ammo and some Very Cartridges)

Its light wing loading made it an excellent gun platform at high altitudes. Could easy

outclimb and outturn an Albatros D.II. The ceiling of the Pup at 5200m was 700m

above the calculated ceiling of the Albatros D.II.

August 1917 also used as Home Defence fighter against Gotha bombers

Gap : 1.34m chord : 1.56m petrol capacity : 18 gallon = 82 litre oil : 5 gallon = 22.7 litre

Climb to 1524m : 7 min 40 sec , climb to 3048m : 15 min 24 sec

users : RNAS, RFC

crew : 1

armament : 1 synchronized 7.70 [mm] (0.303 in) Vickers machine-gun

engine : 1 Le Rhone 9c air-cooled 9 -cylinder two-valve rotary engine 90 [hp](66.2 KW)

dimensions :

wingspan : 8.08 [m], length : 5.89 [m], height : 2.87[m]

wing area : 23.6 [m^2]

weights :

max.take-off weight : 556 [kg]

empty weight operational : 358 [kg] bombload : 0 [kg]

performance :

maximum speed : 170 [km/hr] at sea-level

climbing speed : 218 [m/min]

service ceiling : 5182 [m]

endurance : 2.93 [hours]

estimated action radius : 224 [km]

description :

1-bay biplane with fixed landing gear and tail strut

two spar upper and lower wing

engines, landing gear, fuel and bombs in or attached to the fuselage

airscrew :

fixed pitch 2 -bladed tractor airscrew with max. efficiency :0.66 [ ]

estimated diameter airscrew 2.57 [m]

angle of attack prop : 19.80 [ ]

reduction : 1.00 [ ]

airscrew revs : 1300 [r.p.m.]

pitch at Max speed 2.18 [m]

blade-tip speed at Vmax and max revs. : 181 [m/s]

Afbeeldingsresultaat voor Sopwith Pup

calculation : *1* (dimensions)

mean wing chord : 1.46 [m]

calculated wing chord (rounded tips): 1.68 [m]

wing aspect ratio : 5.53 []

gap : 1.34 [m]

gap/chord : 0.92 [ ]

seize (span*length*height) : 137 [m^3]

calculation : *2* (fuel consumption)

oil consumption : 4.3 [kg/hr]

fuel consumption(cruise speed) : 18.0 [kg/hr] (24.5 [litre/hr]) at 63 [%] power

distance flown for 1 kg fuel : 8.51 [km/kg]

estimated total fuel capacity : 82 [litre] (60 [kg])

calculation : *3* (weight)

weight engine(s) dry : 122.0 [kg] = 1.84 [kg/KW]

weight 19 litre oil tank : 1.6 [kg]

oil tank filled with 0.5 litre oil : 0.4 [kg]

oil in engine 0 litre oil : 0.3 [kg]

fuel in engine 0 litre fuel : 0.3 [kg]

weight 10 litre gravity patrol tank(s) : 1.6 [kg]

weight cowling 2.6 [kg]

weight airscrew(s) (wood) incl. boss & bolts : 15.2 [kg]

total weight propulsion system : 143 [kg](25.6 [%])

***************************************************************

fuselage skeleton (wood gauge : 4.93 [cm]): 37 [kg]

bracing : 1.5 [kg]

fuselage covering ( 6.6 [m2] doped linen fabric) : 2.1 [kg]

weight controls + indicators: 5.2 [kg]

weight seats : 3.0 [kg]

weight other details, lighting set, etc. : 5.1 [kg]

weight 71 [litre] main fuel tank empty : 5.7 [kg]

weight engine mounts & firewalls : 3 [kg]

total weight fuselage : 63 [kg](11.3 [%])

***************************************************************

weight wing covering (doped linen fabric) : 15 [kg]

total weight ribs (31 ribs) : 33 [kg]

load on front upper spar (clmax) per running metre : 562.3 [N]

Afbeeldingsresultaat voor Sopwith Pup

load on rear upper spar (vmax) per running metre : 187.5 [N]

total weight 8 spars : 21 [kg]

weight wings : 69 [kg]

weight wing/square meter : 2.93 [kg]

weight 4 interplane struts & cabane : 6.3 [kg]

weight cables (41 [m]) : 1.4 [kg] (= 33 [gram] per metre)

diameter cable : 2.3 [mm]

weight fin & rudder (0.8 [m2]) : 2.3 [kg]

weight stabilizer & elevator (2.7 [m2]): 8.0 [kg]

total weight wing surfaces & bracing : 87 [kg] (15.7 [%])

*******************************************************************

weight machine-gun(s) : 15.9 [kg]

weight ammunition magazine(s) :1.8 [kg]

weight synchronizing system : 1.0 [kg]

weight armament : 19 [kg]

********************************************************************

wheel pressure : 278.0 [kg]

weight 2 wheels (710 [mm] by 79 [mm]) : 14.5 [kg]

weight tailskid : 1.4 [kg]

weight undercarriage with axle 12.2 [kg]

total weight landing gear : 28.2 [kg] (5.1 [%]

*******************************************************************

Afbeeldingsresultaat voor Sopwith Pup

********************************************************************

calculated empty weight : 339 [kg](61.0 [%])

weight oil for 3.5 hours flying : 15.1 [kg]

weight ammunition (400 rounds) : 13.6 [kg]

weight Very pistol with cartridges : 3.6 [kg]

weight automatic pistol with spare magazines : 1.2 [kg]

*******************************************************************

calculated operational weight empty : 373 [kg] (67.0 [%])

published operational weight empty : 358 [kg] (64.4 [%])

_____________

| o |

-------------

"

weight crew : 81 [kg]

weight fuel for 1.5 hours flying : 27 [kg]

********************************************************************

operational weight : 481 [kg](86.4 [%])

estimated bomb load : 25 [kg]

operational weight bombing mission : 506 [kg]

fuel reserve : 33 [kg] enough for 1.83 [hours] flying

possible additional useful load : 18 [kg]

operational weight fully loaded : 556 [kg] with fuel tank filled for 100 [%]

published maximum take-off weight : 556 [kg] (100.0 [%])

||

I||==|

||

calculation : * 4 * (engine power)

power loading (operational without bombload) : 7.26 [kg/kW]

total power : 66.2 [kW] at 1300 [r.p.m]

Afbeeldingsresultaat voor Sopwith Pup

calculation : *5* (loads)

manoeuvre load : 4.3 [g] at 1000 [m]

limit load : 4.5 [g] ultimate load : 6.8 [g] load factor : 2.3 [g]

design flight time : 2.34 [hours]

design cycles : 277 sorties, design hours : 650 [hours]

operational wing loading : 200 [N/m^2]

wing stress (3 g) during operation : 204 [N/kg] at 3g emergency manoeuvre

calculation : *6* (angles of attack)

angle of attack zero lift : -1.56 ["]

max. angle of attack (stalling angle) : 12.95 ["]

angle of attack at max. speed : 0.36 ["]

calculation : *7* (lift & drag ratios

lift coefficient at angle of attack 0° :0.12 [ ]

lift coefficient at max. angle of attack : 1.12 [ ]

lift coefficient at max. speed : 0.15 [ ]

induced drag coefficient at max. speed : 0.0022 [ ]

drag coefficient at max. speed : 0.0287 [ ]

drag coefficient (zero lift) : 0.0265 [ ]

calculation : *8* (speeds

stalling speed at sea-level (OW): 62 [km/u]

landing speed at sea-level (OW without bombload): 74 [km/hr]

min. drag speed (max endurance) : 104 [km/hr] at 2591 [m](power :37 [%])

min. power speed (max range) : 107 [km/hr] at 2591 [m] (power:38 [%])

max. rate of climb speed : 102.1 [km/hr] at sea-level

cruising speed : 153 [km/hr] op 2591 [m] (power:63 [%])

design speed prop : 165 [km/hr]

maximum speed : 170 [km/hr] op 100 [m] (power:99 [%])

climbing speed at sea-level (without bombload) : 296 [m/min]

Afbeeldingsresultaat voor Sopwith Pup

Sopwith Pup, captured by the Germans

calculation : *9* (regarding various performances)

take-off distance at sea-level : 115 [m]

lift/drag ratio : 9.60 [ ]

max. practical ceiling : 5650 [m] with flying weight :444 [kg]

practical ceiling (operational weight): 5200 [m] with flying weight :481 [kg]

practical ceiling fully loaded (mtow- 1 hour fuel) : 4550 [m] with flying weight :538 [kg]

published ceiling (5182 [m]

climb to 1500m (without bombload) : 5.64 [min]

climb to 3000m (without bombload) : 13.77 [min]

max. dive speed : 355.4 [km/hr] at 3550 [m] height

load factor at max. angle turn 2.03 ["g"]

turn radius at 500m: 36 [m]

time needed for 360* turn 9.1 [seconds] at 500m

calculation *10* (action radius & endurance)

operational endurance : 3.33 [hours] with 1 crew and 43 [kg] useful (bomb)load and 100.0 [%] fuel

published endurance : 2.93 [hours] with 1 crew and possible useful (bomb) load : 50 [kg] and 88.1 [%] fuel

action radius : 350 [km] with 1 crew and 20[kg] photo camera/radio transmitter or bombload

max range theoretically with additional fuel tanks for total 165 [litre] fuel : 1027 [km]

useful load with action-radius 250km : 62 [kg]

production : 9.48 [tonkm/hour]

oil and fuel consumption per tonkm : 2.35 [kg]

_

I_°==/

°

Literature :

prakt. handb. vliegt. deel 1 page183

tussen vleugels van linnen page 55

Jane's FAWOI page 83,85

jagdflugzeuge WO I page 35

oorlogsvliegtuigen 14-18 page 69

warplanes WOI page 18,56,59,62,74,94,95

fighters 1914-19 page 67

Afbeeldingsresultaat voor Sopwith Pup

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 21 August 2019 contact : info.aircraftinvestigation@gmail.com python 3.7.4