O.Thetford, P.Gray German Aircraft of the First World War (Putnam)

Zeppelin-Staaken Type "L" Seaplane
   This machine, which was allocated the Naval No. 1432, was virtually an R VI type mounted upon massive duralumin floats some 13 m. (42 ft. 7 7/8 in.) in length, divided into twelve water-tight compartments. The aircraft was wrecked during trials. Engines, four 260 h.p. Mercedes D IVa. Span, 42.2 m. (135 ft. 5 5/8 in.). Length, 22.2 m. (72 ft. 10 3/8 in.). Height, 7.38 m. (24 ft. 2 5/8 in.). Area, 360 sq.m. (3,888 sq.ft.). Weights: Empty, 8,400 kg. (18,480 lb.). Loaded, 11,800 kg. (25,960 lb.). Speed, 125 km.hr. (78.125 m.p.h.). Climb, 1,780 m. (5,839 ft.), in 60 min. Ceiling, 2,500 m. (8,200 ft.). Duration, 10 hr. Armament, four machine-guns.

G.Haddow, P.Grosz The German Giants (Putnam)

Staaken L

   The German Navy's interest in R-planes did not wane with the destruction of its RML.1; on the contrary, Naval authorities actively continued to pursue the development of R-planes for use in naval warfare. As early as December 1916, Rear Admiral Philipp, Befehlshaber der Luftstreikrafte (Chief of Air Forces), had outlined future naval requirements and had established preliminary specifications as guidelines for aircraft manufacturers.
   The reason for the increased emphasis on R-seaplanes was that English aircraft were very successful in attacking German airships. This resulted in a standing order that airships were to remain above 13,000 feet, which precluded their use as low-level submarine, shipping and mine spotters. Taking this into account, Admiral Philipp recommended the development and evaluation of less-vulnerable R-seaplanes of the flying-boat and floatplane category. Admiral Philipp listed the R-planes' advantages over the airship, as follows: they could fly faster, carry greater defensive armament, did not require huge hangars, could be readied for flight in a fraction of the time, used less personnel and were cheaper to build. The preliminary specifications for three classes of giant seaplanes were outlined in Admiral Philipp's memorandum of 26 December 1916:
   I. Reconnaissance Aircraft
   (a) 1200 h.p. (four engines).
   (b) Five crew, four machine-guns, wireless equipment, 100 kg. bombs, 10-12 hours duration.
   (c) Rapid climb not required.
   (d) Slow climb with one engine stopped, must maintain altitude on two engines.
   (e) Take-off capability required in dead calm, wind and sea.
   Take off in "Seegang 3" (wave height 3/4-2 metres, wind force 4)
   Landing in "Seegang 6" (wave height 5-7 metres, wind force 7-8)
   II. Bomber Aircraft (four engines)
   (a) Five crew, five machine-guns, wireless equipment, 1000-1800 kg. bombs, 5 hours duration.
   (b) Minimum speed 130 km.h.
   (e) Good climb.
   (d) As in I(d).
   (e) As in I(e).
   III. Torpedo Aircraft (four engines)
   (a) Five crew, two machine-guns, wireless equipment, one G-Torpedo (1020 kg.), 8 hours duration.
   (b) Maximum speed 130 km.h., minimum speed 80 km.h.
   (e) Rapid climb not required.
   (d) Slow climb with one engine cut. Must maintain altitude on two engines after torpedo has been dropped and with 2 hours fuel aboard.
   (e) As in I(e)
   Admiral Philipp went on to say: "Most urgent is the development of the reconnaissance R-plane." This statement was supported by a fair number of letters and notes in which high-ranking naval officers pressed for the immediate development of large reconnaissance aircraft for low-altitude spotting duties which the airship could no longer fulfil.
   In a document dated 10 February 1917 Philipp defines more precisely the future role of the R-seaplane. Because the R-seaplane will be required to fly but 500 metres over the water, Philipp said, it must be endowed with greater reliability than any other type of aircraft, as a slight mechanical failure could force it down far out at sea. The projected task was low-level reconnaissance, primarily for mine-spotting, shipping control and anti-submarine duties.
   On 26 December 1916 a report of Oberlt. z. S. Mans, who had just returned from an inspection of the Dornier R-flying-boat, ends with the comment that Luftschiffbau Zeppelin is to present a new proposal to meet the above-mentioned reconnaissance requirements. It should be noted that during the war only two companies, Staaken and Dornier, both part of the Zeppelin combine, delivered R-seaplanes to the Navy.
   Staaken proposed a floatplane version of the Staaken R.VI, designated Staaken L, which was ordered by the German Navy on 15 February 1917 and assigned Navy number 1432. Upon completion in August 1917, the Staaken L, fitted with a standard R.VI wheeled undercarriage, was flown to the company's seaplane testing site at Potsdam where floats were mounted. On 5 September 1917 it was launched for the first time and promptly made two short flights. Modifications made during flight testing included replacing the narrow four-bladed pusher propellers by standard two-bladed ones, adding a central fin to increase directional stability and reinforcing the float structure with extra struts. On 12 November 1917, the Staaken L left Potsdam on a cross-country delivery flight but owing to failure of one engine, was forced to land at Saaler Bodden, some 40 km east of Warnemunde. After repairs were made, the Staaken L was delivered to the Navy on 14 November 1917.
   Apart from its floats, the Staaken L differed little from the standard Staaken R.VI. Minor changes included a 1 1/2 degree sweepback starting at the centre line. The ailerons were aerodynamically balanced by large overhanging areas at the wingtips, and their chord was increased to counteract the lateral resistance of the floats. The total wing area, including ailerons, was increased to 360 square metres, and the fuselage bomb-bay fairing of the Staaken R.VI machines was eliminated.
   The large all-duraluminium floats were extensively compartmented, so that in the event of springing a leak or receiving bullet holes, they would retain their buoyancy. The floats were attached by steel struts to the wing below the engine nacelles, and the absence of cross-bracing between the floats suggests the possibility that the area under the fuselage was left clear to provide means for evaluating the Staaken L as a bombing or torpedo plane at some later date. Indeed, the aircraft is classified as a bomber in official Navy documents.
   Fourteen 245 litre fuel tanks in the fuselage, two 150 litre tanks in each engine nacelle and a 155 litre overhead gravity tank provided sufficient fuel for 10 hours cruising on all engines. During evaluation tests a technique was developed to extend the range by cruising on only three engines, provided enough fuel had been consumed to reduce the machine's weight.
   The Staaken L was equipped with Navy-developed transmitting and receiving gear, which was powered by a propeller-driven generator mounted above the wireless operator's compartment in contrast to the Army wireless equipment, which required a motor-driven generator. The aircraft was assigned to the Seeflugzeug-Versuchs-Kommando (Seaplane Testing Command) in Warnemunde for extensive tests and evaluation over a wide range of sea and weather conditions.
   A special wooden hangar was designed and constructed by Firma Carl Tuchscherer in 1917 to house the Staaken L. Built on piles over the water, the hangar was unique in that the door was only 27•5 metres wide. A larger door capable of withstanding high seas and winds would have been difficult to install and maintain. Therefore, to keep the door small, it was decided to bring the aircraft into the hangar sideways, using a novel technique. Experiments had proved the impracticability of bringing an aircraft into a hangar sideways under even the slightest wind and wave conditions. Consequently, Tuchscherer proposed and built a pivoted, floating pier extending at right angles from one side of the hangar opening. The aircraft's left float was secured to the floating pier. Then the pier was swung around, its pivoted end turning the aircraft sideways through the opening into the hangar as it completed a 180 degree arc. The hangar trusses were capable of supporting a 12,000 kg. load, permitting the Staaken L to be lifted for repairs to the floats. A second, much larger hangar capable of housing four R-planes was under construction at the close of the war.
   The Staaken L crashed over Warnemunde on 3 June 1918 killing the pilot, Lt. Haller and the crew. (The Report of the Aircraft Section of the Allied Naval Armistice Commission states: "The 1432 crashed on its trials at Warnemunde owing to the engines failing whilst over the land, and the crew including Kapt. Lt. Kirsch, who was in charge of wireless experimental work, were killed.") Very little is known regarding the outcome of the Staaken L evaluation tests. It was not as stable on the water as the Dornier R-flying-boat . The wing tips would touch the water at a 7 degree heel, whereas the flying-boat required a 14 degree heel. Nevertheless, it was a proven design that Staaken had built in quantity, and it could be produced in less time than the all-metal Dornier flying-boats. Six further Staaken R-seaplanes based on the Staaken L were ordered by the Navy.

Colour Scheme and Markings

   The Staaken L was finished overall in a light colour and carried the Patee cross insignia outlined in white on wings, fuselage and tail. Contrary to usual Naval practice, the serial number was not painted on the fuselage. At Potsdam the Staaken L was named "Lisbet" and this name was painted in black capital on both sides of the fuselage.


SPECIFICATIONS

Type: Staaken L
   Manufacturer: Flugzeugwerft G.m.b.H., Staaken, Berlin
   Engines: Four 260 h.p. Mercedes D.IVa engines
   Dimensions:
   Span, 42•2 m. (138 ft. 5 1/2 in.)
   Maximum Chord, 4•53 m. (14 ft. 10 in.)
   Maximum Gap, 4•55 m. (14 ft. 11 in.)
   Length, 22•2 m. (72 ft. 10 in.)
   Height, 7•38 m. (24 ft. 2 1/2 in.)
   Propeller diameter, 4-4 m. (14 ft. 5 in.)
   Propeller centres, 8 m. (26 ft. 3 in.)
   Float length, 12 m. (39 ft. 4 1/2 in.)
   Areas: Wings, 360 sq. m. (3874 sq. ft.)
   Weights:
   Empty, 8400 kg. (18,522 lb.)
   Loaded, 11,800 kg. (26,019 lb.)
   Floats, 600 kg. (1323 lb.)
   Fuel, 2445 kg. (5391 lb.)
   Wing Loading: 32.77 kg./sq. m. (6'7 lb./sq. ft.)
   Performance:
   Maximum speed, 125 km.h. (77,7 m.p.h.)
   Landing speed, 85 km.h. (52'8 m.p.h.)
   Climb with full load,
   1000 m. (3281 ft.) in 23•7 mins.
   1780 m. (5840 ft.) in 60 mins.
   Ceiling, 2500 m. (8202 ft.)
   Duration, 10 hrs.
   Fuel:
   3395 litres (747 Imp. Gals.)
   Oil, 320 litres (70-4 Imp. Gals.)
   Armament: Provisions for nose, dorsal and ventral machine-gun positions
   Service Use: None

J.Herris Zeppelin-Staaken Aircraft of WW1. Vol 1: VGO.1 - R.IV R.29/16 (A Centennial Perspective on Great War Airplanes 47)

Staaken Specifications
Type R.XVI L 8301 & 8303
Engines 2x500 Hp Benz Bz.VI 2x220 Hp Benz Bz.FV 4x260 Hp Mercedes D.IVa 4x260 Hp Mercedes D.IVa
Span 42.2 m (138' 5 1/2") 42.2 m (138' 5 1/2") 42.2 m (138'5 1/2")
Chord (max.) - 4.53 m( 14' 10") -
Gap (max.) - 4.55 m (14' 11") -
Length 22.5 m (73' 10") 22.2 m (72' 10") 21 m (68' 10 1/2")
Height 6.5 m (21'4") 7.38 m (24' 2 1/2") 6.8 m (22'3 1/2")
Wing Area 340 m2 (3,658 ft2) 360 m2 (3,874 ft2) 340.5 m2 (3,663 ft2)
Wt. Empty 10,400 kg (22,932 lb.) 8,400 kg (18,522 lb.) 9,000 kg (19,845 lb.)
Wt. Fuel - 2,445 kg (5,391 lb.) -
Wt. Loaded 14,650 kg (32,303 lb.) 11,800 kg (26,019 lb.) 12,500 kg (27,563 lb.)
Max Speed 130 km/h (80.8 m/h) 125 km/h (77.7 m/h) 130 km/h (80.8 m/h)
Climb 1,000 m - 23.7 minutes (full load) -
Climb 1,780 m - 60 minutes -
Ceiling 3,710 m 2,500 m -
Duration - 10 hours -
The Staaken L & 8301/8303 were naval floatplanes derived from the R.VI. The 8301 & 8303 could climb to 3,000 m in 54 minutes.

J.Herris Zeppelin-Staaken Aircraft of WW1. Vol 2: R.VI R.30/16 - E.4/20 (A Centennial Perspective on Great War Airplanes 48)

Staaken L

  The German Navy had an increasing need for a long-range, high-endurance seaplane despite the crash of the R.M.L.1. This military requirement was driven by the increasing success of the British America/Felixstowe flying boats against the German airships. Additional advantages of large seaplanes over airships included being faster and more heavily armed, cheaper, and could use smaller hangars, required fewer support personnel, and had faster response time. The primary task was to be low-altitude reconnaissance for mine-spotting, antisubmarine warfare, and shipping control; the low planned cruising altitude of 500 m demanded greater reliability than any other aircraft type.
  Only two companies, Zeppelin-Staaken and Zeppelin-Lindau, delivered R-seaplanes to the German Navy. A report of 26 December 1916 by Oblt.z.S Mans, who had just visited Zeppelin-Lindau to inspect the all-metal Dornier R-type flying boat prototype then under construction, noted that Staaken was planning to propose a new R-type seaplane. This proposal was the Staaken L. The German Navy ordered an example of this aircraft on February 15, 1917, and assigned it the Marine Number 1432. This aircraft was delivered on November 14, 1917.
  The Staaken L, designed as a floatplane derivative of the R.VI, was built as a landplane, most likely to facilitate flight-testing at the factory and its delivery flight to Potsdam where the floats were fitted. During taxi trials there a number of modifications were made; a central fin was added to improve stability, standard two-bladed pusher propellers replaced the four-bladed pusher propellers, and the floats were reinforced.
  Apart from being a floatplane, the Staaken L was very similar to the R.VI. The wing area was increased and the ailerons were enlarged and balanced. The all-duralumin floats were highly compartmentalized to retain buoyancy in case of damage. The float struts were made of steel. The Navy classed the Staaken L as a bomber, and the lack of cross-bracing between the float struts indicates that carriage of torpedoes was considered a possibility.
  The fuel tanks were the 245 liter type used in the R.VI, but instead of the 8 or 10 used in the R.VI, 14 were installed in the Staaken L. Additional fuel was carried in two 150 liter tanks in each nacelle and a 155 liter gravity tank as used in the R.VI. The fuel load enabled a 10-hour endurance at cruise speed compared to the 7-hour endurance standard for the R.VI - which did not have the heavy floats of the L. During evaluation flights it was determined that the endurance of the Staaken L could be extended by cruising on only three engines once the Staaken L had burned enough fuel to reduce its weight to a certain point. This procedure is used by some modern patrol planes for the same reason.
  Once the Staaken L was completed it was assigned to the SVK (Seeflugzeug-Versuchs-Kommando - Seaplane Testing Command). A special wooden hangar for the Staaken L was built for the aircraft on piles over the water.
  On June 3, 1918 the Staaken L crashed over Warnemunde killing the crew, reportedly after engine failure. The Staaken L was not as stable on the water as the Dornier all-metal R-flying boats; at a 7° heel the tips of the lower wings would touch the water whereas the Dornier R-flying boat accepted a 14° heel before its wingtips would touch the water. However, the Staaken L was based on a proven design and was far easier to produce than the metal Dornier flying boats.