The concept was hit upon after Norddeutscher Lloyd (NDL) had carried a Junkers F.13 seaplane aboard the Lutzow during 1927 to provide joyrides for passengers when the liner was in port. NDL officials realised that a seaplane based on a liner could have a more practical commercial application, taking off with the liner’s airmail while still a long distance from port, therefore drastically cutting down time taken for the mail to arrive. Heinkel designed a catapult, which NDL planned to install on its new liners, the Bremen and Europa, and an aircraft to carry the mail. Since the crew of Lutzow had trouble providing the necessary maintenance for the F 13, Deutsche Luft Hansa agreed to provide the operational support for the venture, and when Bremen departed on her maiden voyage in 1929, a single HE 12 (D-1717) was carried aboard.
A second aircraft, (D-1919, Atlantik), was built for flying from Europa, sister-ship of the Bremen. Designated He 58, the second aircraft was slightly larger overall than the He 12, with increased payload and accommodation for the crew in a side-by-side open cockpit. Power was supplied by a 370 kW (500 hp) BMW Hornet A, initially un-cowled, but later fitted with a full long-chord cowling with cooling slits in the forward face.
The He 58, (D-1919, Atlantik), continued in service on Europa until replaced by Junkers Ju 46 floatplanes.
He 58
Engine: 70 kW (500 hp) BMW Hornet A
Wingspan: 17.2022 m (56 ft 5.25 in)
Wing area: 49.4 m2 (532 sq ft)
Length: 11.7793 m (38 ft 7.75 in)
Height: 4.70 m (15 ft 5 in)
Empty weight: 1,850 kg (4,078 lb)
Gross weight: 3,140 kg (6,922 lb)
Payload: 200 kg (440 lb) of mail
Maximum speed: 204 km/h (127 mph)
Cruise speed: 159 km/h (99 mph)
Service ceiling: 3,800 m (12,500 ft)
Crew: Two, pilot and radio operator
All Aero 