Aircraft investigation >>>>>>> HOME PAGE

weight and performance calculations for the Voisin 10 LA.R

Afbeeldingsresultaat voor Voisin LAR

Voisin 10 LA.R

role : light bomber

importance : ****

first flight : operational : February 1918

country : France

design :

production : 900 aircraft

general information :

The Peugeot engine in the Voisin 8 was not reliable, so it was replaced with a 280 hp Renault V12 engine which also gave better performance at altitude. This version was designated Voisin 10 LAR. There was also a Canon/version with a 37mm canon ,marked as LBR but that was used only on small scale.

users : France

crew : 2

armament : 1 movable 7.70 [mm] (0.303 in) Lewis machine-gun for the observer

engine : 1 Renault 12 Fe liquid-cooled 12 -cylinder V-engine 280 [hp](205.9 KW)

Afbeeldingsresultaat voor Voisin LAR

dimensions :

wingspan : 18.0 [m], length : 11.0 [m], height : 3.5[m]

wing area : 63.2 [m^2]

weights :

max.take-off weight : 2050 [kg]

empty weight operational : 1400 [kg] bombload : 300 [kg]

performance :

maximum speed : 130 [km/hr] at sea-level

service ceiling : 4000 [m]

endurance : 4.0 [hours]

estimated action radius : 234 [km]

description :

3-bay biplane with fixed landing gear with nosewheel

two spar upper and lower wing

tail supported by two open tail booms

engine, landing gear and bombload in or attached to fuselage, fuel in/on the wing

airscrew :

fixed pitch 2 -bladed pusher airscrew with max. efficiency :0.64 [ ]

estimated diameter airscrew 3.53 [m]

angle of attack prop : 12.25 [ ]

fine pitch

reduction : 0.75 [ ]

airscrew revs : 1200 [r.p.m.]

pitch at Max speed 1.81 [m]

blade-tip speed at Vmax and max revs. : 225 [m/s]

calculation : *1* (dimensions)

mean wing chord : 1.76 [m]

calculated wing chord (rounded tips): 1.89 [m]

wing aspect ratio : 10.25 []

estimated gap : 1.45 [m]

gap/chord : 0.83 [ ]

seize (span*length*height) : 693 [m^3]

calculation : *2* (fuel consumption)

oil consumption : 4.3 [kg/hr]

fuel consumption(cruise speed) : 50.2 [kg/hr] (68.5 [litre/hr]) at 65 [%] power

distance flown for 1 kg fuel : 2.33 [km/kg]

estimated total fuel capacity : 311 [litre] (228 [kg])

calculation : *3* (weight)

weight engine(s) dry : 411.9 [kg] = 2.00 [kg/KW]

weight reduction gear : 10.3 [kg]

weight 28 litre oil tank : 2.4 [kg]

Afbeeldingsresultaat voor Voisin LAR

oil tank filled with 1.5 litre oil : 1.4 [kg]

oil in engine 11 litre oil : 10.3 [kg]

fuel in engine 1 litre fuel : 1.0 [kg]

weight 29 litre gravity patrol tank(s) : 4.4 [kg]

weight radiator : 29.5 [kg]

weight exhaust pipes & fuel lines 24.9 [kg]

weight self-starter : 5.0 [kg]

weight cowling 8.2 [kg]

weight airscrew(s) (wood) incl. boss & bolts : 30.9 [kg]

total weight propulsion system : 548 [kg](26.7 [%])

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

weight tail boom : 49 [kg]

fuselage skeleton (wood gauge : 7.21 [cm]): 146 [kg]

bracing : 12.8 [kg]

fuselage covering ( 14.9 [m2] doped linen fabric) : 4.8 [kg]

weight controls + indicators: 7.8 [kg]

weight seats : 6.0 [kg]

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

weight bomb storage : 21.0 [kg]

weight Doran/Lafay bomb sight : 1.5 [kg]

weight engine mounts & firewalls : 10 [kg]

total weight fuselage : 216 [kg](10.5 [%])

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

weight wing covering (doped linen fabric) : 40 [kg]

total weight ribs (95 ribs) : 122 [kg]

weight fuel tanks empty for total 141 [litre] fuel : 11 [kg]

Afbeeldingsresultaat voor Voisin LAR

On the outside the 10 LAR differed little from the Voisin 8

load on front upper spar (clmax) per running metre : 825.5 [N]

load on rear upper spar (vmax) per running metre : 309.6 [N]

total weight 8 spars : 173 [kg]

weight wings : 335 [kg]

weight wing/square meter : 5.31 [kg]

weight 12 interplane struts & cabane : 21.8 [kg]

weight cables (103 [m]) : 22.6 [kg] (= 218 [gram] per metre)

diameter cable : 6.0 [mm]

weight fin & rudder (3.8 [m2]) : 20.5 [kg]

weight stabilizer & elevator (6.0 [m2]): 32.5 [kg]

total weight wing surfaces & bracing : 444 [kg] (21.7 [%])

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

weight machine-gun(s) : 12.7 [kg]

weight pivot mounting mg :6.0 [kg]

weight armament : 19 [kg]

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

wheel pressure : 902.0 [kg]

weight 4 wheels (780 [mm] by 98 [mm]) : 46.4 [kg]

weight tailskid : 0.0 [kg]

weight undercarriage with axle 79.5 [kg]

total weight landing gear : 125.9 [kg] (6.1 [%]

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

Afbeeldingsresultaat voor Voisin LAR

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

calculated empty weight : 1352 [kg](66.0 [%])

weight oil for 4.8 hours flying : 20.8 [kg]

weight cooling fluids : 44.5 [kg]

weight 5 drums empty : 1.0 [kg]

weight ammunition (235 rounds) : 7.5 [kg]

weight signal pistol with cartridges : 3.6 [kg]

weight automatic pistol with spare magazines : 1.2 [kg]

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

calculated operational weight empty : 1430 [kg] (69.8 [%])

published operational weight empty : 1400 [kg] (68.3 [%])

_____________

| | |o| | |

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

"

""

weight crew : 162 [kg]

weight fuel for 2.0 hours flying : 100 [kg]

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

operational weight : 1692 [kg](82.6 [%])

bomb load : 300 [kg]

operational weight bombing mission : 1992 [kg]

fuel reserve : 58 [kg] enough for 1.15 [hours] flying

operational weight fully loaded : 2050 [kg] with fuel tank filled for 69 [%]

published maximum take-off weight : 2050 [kg] (100.0 [%])

||

||

=||I>|

||

||

calculation : * 4 * (engine power)

power loading (Take-off) : 9.95 [kg/kW]

total power : 205.9 [kW] at 1600 [r.p.m]

calculation : *5* (loads)

manoeuvre load : 1.6 [g] at 1000 [m]

limit load : 3.0 [g] ultimate load : 4.5 [g] load factor : 2.0 [g]

design flight time : 3.20 [hours]

design cycles : 422 sorties, design hours : 1350 [hours]

wing loading (MTOW) : 318 [N/m^2]

wing stress (3 g) during operation : 175 [N/kg] at 3g emergency manoeuvre

calculation : *6* (angles of attack)

angle of attack zero lift : -1.11 ["]

max. angle of attack (stalling angle) : 11.28 ["]

angle of attack at max. speed : 2.57 ["]

calculation : *7* (lift & drag ratios

lift coefficient at angle of attack 0° :0.10 [ ]

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

lift coefficient at max. speed : 0.33 [ ]

induced drag coefficient at max. speed : 0.0061 [ ]

drag coefficient at max. speed : 0.0716 [ ]

drag coefficient (zero lift) : 0.0656 [ ]

calculation : *8* (speeds

stalling speed at sea-level (OW): 70 [km/u]

landing speed at sea-level (OW without bombload): 85 [km/hr]

min. drag speed (max endurance) = minimum speed*1.1 at cruise height : 86 [km/hr] at 2000 [m] (power:40 [%])

min. power speed (max range) : 86 [km/hr] at 2000 [m] (power:40 [%])

max. rate of climb speed : 78.5 [km/hr] at sea-level

cruising speed : 117 [km/hr] op 2000 [m] (power:66 [%])

design speed prop : 124 [km/hr]

maximum speed : 130 [km/hr] op 100 [m] (power:98 [%])

climbing speed at sea-level (without bombload) : 253 [m/min]

calculation : *9* (regarding various performances)

take-off distance at sea-level : 104 [m]

lift/drag ratio : 8.31 [ ]

max. practical ceiling : 4550 [m] with flying weight :1524 [kg]

practical ceiling (operational weight): 4075 [m] with flying weight :1692 [kg]

practical ceiling fully loaded (mtow- 1 hour fuel) : 3250 [m] with flying weight :2000 [kg]

published ceiling (4000 [m]

climb to 1500m (without bombload) : 6.79 [min]

climb to 3000m (without bombload) : 17.84 [min]

max. dive speed : 301.7 [km/hr] at 2250 [m] height

load factor at max. angle turn 1.75 ["g"]

turn radius at 500m: 59 [m]

time needed for 360* turn 12.8 [seconds] at 500m

calculation *10* (action radius & endurance)

operational endurance : 3.15 [hours] with 2 crew and 300 [kg] bombload and 69.4 [%] fuel

published endurance : 4.00 [hours] with 2 crew and possible useful (bomb) load : 257 [kg] and 88.1 [%] fuel

action radius : 511 [km] with 2 crew and 20[kg] photo camera/radio transmitter or bombload

max range theoretically with additional fuel tanks for total 752 [litre] fuel : 1285 [km]

useful load with action-radius 250km : 244 [kg]

production : 28.50 [tonkm/hour]

oil and fuel consumption per tonkm : 1.91 [kg]

_

°°_I>-/

° °

Literature :

Wikipedia

Bombers 1914-19 page 101

Jane’s fighter aircraft WOI page 125

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 23 November 2019 contact : info.aircraftinvestigation@gmail.com python 3.7.4