Navy Aviation Technical Arsenal

Research on High-Speed Long-Range Ship-Based Bomber with the Sole Purpose of Preemptive Strikes on Enemy Carriers

July 1942

High-Speed Long-Range Ship-Based Bomber

  1. Assumptions of Calculations
ArmamentBombsNumber 25 x 1
Machine Guns13mm Flexible Gun x 1 (200 rounds)
Performance RequirementsTop Speed6000 m340 kt [630 km/h] or more
Cruising Capacity230 kt [426 km/h] / 4000 m2000 NM [3704km] or more
Ship TakeoffAt 14 m/s120 m or less
Landing SpeedLight Load70 kt [130 km/h] or less

  1. Calculation Results
EngineNK9HNK9HAE1TMA20 Performance Improvement Model w/ Vulkan for Fighters
Rated Power / Altitude1700hp / 6km1700hp / 6km1250hp / 8km
(1350hp / 6km)
1970hp / 6km
Dimensions (Width x Length x Height)12.5 x 10.5 x 3.8m12 x 10 x 3.8m11.5 x 10.5 x 3.7m13 x 11 x 3.9m
Main Wing Surface Area26.5m224.5m222m228m2
WeightNormal Load (Wing Loading)4700kg (177kg/m2)4500kg (184kg/m2)4600kg (209kg/m2)5150kg (184kg/m2)
Overload (Wing Loading)5300kg (200kg/m2)5050kg (206kg/m2)5200kg (236kg/m2)5800kg (207kg/m2)
Light Load (Wing Loading)4020kg (152kg/m2)3725kg (152kg/m2)3910kg (177kg/m2)4325kg (154kg/m2)
Empty Weight (Wing Loading)3175kg2925kg3120kg3450kg
Fuel and OilNormal Load750kg800kg780kg (600kg)   fuel tank difficulties820kg
Over Load1300kg1300kg1330kg1[?]20kg
Fixed Equipment Weight (including protection)830kg700kg830kg830kg
PerformanceTop Speed340kt [630km/h] / 6km345kt [639km/h] / 6km360kt [667km/h] / 8km
(340kt [630km/h] / 6km)
Same as NK9H with protections
Cruising CapacityConditionNormal LoadOverloadNormal LoadOverloadNormal LoadOverload
230kt [426km/h] / 4km1300NM [2408km]2050NM [3797km]1350NM [2500km]2050NM [3797km]1300NM [2408km]2000NM [3704km]
200kt [370km/h] / 4km1400NM [2593km]2200NM [4074km]1450NM [2685km]2200NM [4074km]1400NM [2593km]2150NM [3982km]
Ship Takeoff12 m/s105m135m105m135m150m200m
14 m/s90m120m90m120m130m180m
Landing Speed (Light Load)70kt [130km/h]70kt [130km/h]75kt [139km/h]
Notes1) Protection:
Pilot seat, 10mm steel plate.
Fuel tank, against 13mm MG.
Total weight estimated at 130kg

2) Cruising capacity when equipped with No. 50 (takeoff performance is the same):
230kt [426km/h] / 4km, 1650 NM
200kt [370km/h] / 4km, 1770 NM
If the top speed is 340 kt [630 km/h], the wing surface area is too small, and the cruising capacity, takeoff and landing performance are affected.Performance is not much different than NK9H, but the weight and dimensions become excessive.

  1. Comparison with Each Plane Model
Plane ModelHigh-Speed Long-Range Ship-Based BomberD4A30N50
ArmamentBombsNumber 25 x 1Number 25 x 1Number 50 x 1
Machine GunsFixed7.7mmx2 (400x2)same as left
Flexible13mm x 1 (200)7.7mm x 1 (6 mags)7.7mm x 1 (6 mags)
Situation A Load Factor7g7g6.5g3.5g
EngineNK9HAE1A Performance ImprovedNK9HNK9H
High Rated Power / Altitude1700hp / 6km1200hp / 3700m(1460 / 5800)
1700hp / 6km
1700hp / 6km
Dimensions (Width x Length x Height)12.5 x 10.5 x 3.8m11.5 x 10.2 x 3.65m14.4 x 11.5 x 3.8m12.5 x 11 x 3.7m
Main Wing Surface Area26.5m223.6m235.5m225.5m2
WeightNormal Load (Wing Loading)4700kg (177kg/m2)3650kg (155kg/m2)4950kg (139kg/m2)4500kg (176kg/m2)
Overload (Wing Loading)5300kg (200kg/m2)4500kg (190kg/m2)5400kg (152kg/m2)5300 (208kg/m2)
Light Load (Wing Loading)4020kg (152kg/m2)3090kg (131kg/m2)
Empty Weight (Wing Loading)3175kg2440kg
Fuel and OilNormal Load750kg505kg670kg870kg
PerformanceTop Speed0285kt [528km/h]265kt [491km/h]255kt [472km/h]288kt [533km/h]
2000310kt [574km/h]285kt [528km/h]275kt [509km/h]313kt [580km/h]
Rated Altitude340kt [630km/h] / 6km305kt [565km/h] / 4km
(325kt [602km/h] / 5.5km AE1P)
315kt [583km/h] / 6km345kt [639km/h] / 6km
Cruising CapacityConditionNormal LoadOverloadNormal LoadOverloadNormal LoadOverloadNormal LoadOverload
230kt [426km/h] / 4km1300NM [2408km]2050NM [3797km](3000m)
850NM [1574km]
1900NM [3519km]
1410NM [2611km]2220NM [4111km]
200kt [370km/h] / 4km1400NM [2593km]2200NM [4704km]900NM [1667km]2000NM [3704km]1000NM [1852km]1800NM [3334km]210kt [389km/h] / 4km
1540NM [2852km]
210kt [389km/h] / 4km
2590NM [4797km]
Takeoff12 m/s105m135m85m170m75m
14 m/s90m120m75m150m
Landing SpeedLight Load70kt [130km/h]Normal Load75.5kt [140km/h]Normal Load65kt [120km/h]Normal Load 70kt [130km/h]¼ Fuel and Oil
65kt [120km/h]
NotesWith protection.
Weight 130kg.
Without protection.Inside ( ) is with NK9B.
Without protection.
With protection.
Weight 160kg.

(4)Performance When Loaded with a Number 50

EngineDesignationNK9HMA20 Performance Improvement Model w/ Vulkan for Fighters
Takeoff Power2000hp2300hp
Rated Power / Altitude1700hp / 6km1970hp / 6km
Dimensions (Width x Length x Height)12.5 x 10.5 x 3.8m13 x 11 x 3.9m
Main Wing Surface Area26.5m228.0m2
Gross Weight4700kg5150kg
Top Speed340kt [630km/h] / 6km340kt [630km/h] / 6km
Cruising Capacity (Overload)BombsNo. 25No. 50No. 50No. 25No. 50No. 50
Fuel and Oil1300kg1050kg1300kg1420kg1170kg1420kg
Cruising Range250kt [463km/h] / 4km1800NM [3334km]1450NM [2685km]1700NM [3148km]1800NM [3334km]1480NM [2741km]1700NM [3148km]
230kt [426km/h] / 4km2050NM [3797km]1650NM [3056km]1950NM [3611km]2050NM [3797km]1690NM [3130km]1950NM [3611km]
200kt [370km/h] / 4km2200NM [4074km]1770NM [3278km]2100NM [3889km]2200NM [4074km]1810NM [3352km]2100NM [3889km]
Ship Takeoff RunCombined Wind Speed12m/s135m135m155mSame as left

(5) Notes

  1. The equipment weight is the same as the 13-Shi Ship-Based Bomber [(D4Y)], except for the 7.7mm fixed machine gun x 2 and 7.7mm flexible machine gun x 1, which is changed to a 13mm flexible machine gun.
  2. For protection the pilot has a 10mm steel plate, the fuel tank is protected against 13mm machine guns, and the total weight is estimated at 130 kg.
  3. About ⅔ of the cruising capacity depends on internal fuel tanks. About ⅓ is from drop tanks.
  4. The weight of methanol loaded is equivalent to 30 minutes of rated power.
  5. In the condition of loading a Number 50, the degree of strength is exceeded somewhat, so operational restrictions are required.