HE 8, HE 31 and HM.II
Orlogsvaerftet HM.II of the Royal Danish Navy
Role	Reconnaissance floatplane Type of aircraft
National origin	Germany
Manufacturer	Heinkel
First flight	1927
Primary user	Danish Navy
Number built	22

The Heinkel HE 8 was a reconnaissance floatplane built in Germany in the late 1920s. It was developed at the request of the Danish Navy, which had noted the success of the HE 5 in Swedish service, and wished to purchase a similar aircraft as well as licensed production as the Orlogsvaerftet HM.II.^{[citation needed]} Apart from its new Armstrong Siddeley engine, the HE 8 also differed from the HE 5 and previous members of the HE 1 family in having a conventional empennage. 22 aircraft were operated until the German invasion in 1940, after which one example was impressed into Luftwaffe service and the remainder placed in storage.^{[citation needed]}

A single HE 8 was built with a Packard 3A-2500 engine and designated HE 31.

Operators

 Denmark

• Royal Danish Navy

 Yugoslavia

• Royal Yugoslav Navy (One)

Specifications (HM.II)

Data from Jane's all the World's Aircraft 1931 ^[1]

General characteristics

• Crew: 3
• Length: 11.65 m (38 ft 3 in)
• Wingspan: 16.8 m (55 ft 1 in)
• Height: 4.4 m (14 ft 5 in)
• Wing area: 45 m² (480 sq ft)
• Empty weight: 1,675 kg (3,693 lb)
• Gross weight: 2,650 kg (5,842 lb)
• Powerplant: 1 × Armstrong Siddeley Jaguar 14-cylinder two-row air-cooled geared radial piston engine, 320 kW (430 hp)
• Propellers: 2-bladed fixed-pitch metal propeller

Performance

• Maximum speed: 212 km/h (132 mph, 114 kn)
• Range: 1,290 km (800 mi, 700 nmi)
• Service ceiling: 5,600 m (18,400 ft)
• Rate of climb: 2.8 m/s (550 ft/min)
• Time to altitude: 1,000 m (3,300 ft) in 3 minutes 12 seconds: 5,000 m (16,000 ft) in 28 minutes'
• Wing loading: 61.8 kg/m² (12.7 lb/sq ft)
• Power/mass: 14.2 lb/hp (8.6 kg/kW)

Armament

• Guns: 1 × fixed, forward-firing 8 mm (0.315 in) Madsen machine gun, 1 × trainable, rearward-firing 8 mm (0.315 in) Madsen machine gun
• Bombs: 12 × 0.5 kg (1.1 lb) bombs