https://en.wikipedia.org/wiki/Dornier_Do_217
The Dornier Do 217 was a bomber used by the German Luftwaffe during World War II
as a more powerful development of the Dornier Do 17, known as the Fliegender
Bleistift (German: "flying pencil"). Designed in 1937 and 1938 as a heavy bomber
but not meant to be capable of the longer-range missions envisioned for the
larger Heinkel He 177, the Do 217's design was refined during 1939 and
production began in late 1940. It entered service in early 1941 and by the
beginning of 1942 was available in significant numbers.
The Dornier Do 217 had a much larger bomb load capacity and had much greater
range than the Do 17. In later variants, dive bombing and maritime strike
capabilities using glide bombs were experimented with, considerable success
being achieved. Early Do 217 variants were more powerful than the contemporary
Heinkel He 111 and Junkers Ju 88, having a greater speed, range and bomb load.
Owing to this it was called a heavy bomber rather than a medium bomber. The Do
217 served on all fronts in all roles. On the Eastern Front and Western Front it
operated as a strategic bomber, torpedo bomber and reconnaissance aircraft. It
also performed tactical operations, either direct ground assault or
anti-shipping strikes during the Battle of the Atlantic and Battle of Normandy.
The Do 217 was also converted to become a night fighter and saw considerable
action in the Defence of the Reich campaign until late in the war.
The type also served in anti-shipping units in the Mediterranean, attacking
Allied convoys and naval units during the Battle of the Mediterranean. It was in
the Mediterranean that the Do 217 became the first aircraft in military aviation
history to deploy a form of precision-guided munition in combat, in the form of
the Fritz-X radio-guided, free-fall bomb, which led to the sinking of the
Italian battleship Roma in 1943. After the end of the war, at least one Dornier
Do 217 continued in military operational service with the Swiss Air Force until
1946.
Flying the Do 217 M-1
In October 1945 British Captain Eric Brown undertook full handling trials with a
Do 217 M-1 WNr 56158 at RAF Farnborough. He recalled a distinctly
"underwhelming" experience. Brown recalled that he took off with full power of
some 2,700 rpm and the lightly loaded Do 217M left the runway at 160 km/h (99
mph). Brown held a shallow climb, waiting to reach 200 km/h (120 mph) before
retracting the undercarriage. Brown timed the time it took to retract, which was
between 30 and 40 seconds. At 150 m (490 ft) he reduced power to 2,500 rpm and
raised the flaps at about 230 km/h (140 mph). With the flaps up a climbing speed
of 230 km/h (140 mph) was established giving a rate of "very moderate
proportions".
While in cruising mode, Brown took the Dornier to 5,500 m (18,000 ft) and with
the tail at +2 degrees angle of incidence, gave it a top speed of 523 km/h (325
mph), true air speed. Brown stated the aircraft was very stable about all three
axes, and the controls were well harmonised and effective, and not unduly heavy
for bomber operations. At the other end of the speed range, stall occurred at
154 km/h (96 mph), and was characterised by a gentle nose-down pitch. At this
stage Brown tried the Dornier's single-engine performance and this "proved
decidedly unimpressive". It underlined that the aircraft was underpowered. Above
1,500 m (4,900 ft), height could not be maintained at 2,300 rpm and its ceiling
was barely 7,600 m (24,900 ft). Brown reverted to "normal power", and decided to
"chance his arm" (risk) on a dive-bombing procedure in what he described as a
"ponderous aeroplane". Brown made a straight dive to 700 km/h (430 mph), the
maximum permitted below 3,000 m (9,800 ft) in order to get a feel for the
controls, which began to stiffen considerably. The engine revolutions built to
2,750 during the dive causing a lot of noise. Brown pulled the aircraft out of
its dive though it called for a "good full-blooded heave" on the control column.
After climbing to regain the height lost, Brown decided to test the
tail-mounted, clamshell-like dive brake and automatic pull-out equipment. The
Dornier entered the dive automatically when the dive switch was selected and
soon attained its "braked condition", limiting the airspeed to 575 km/h (357
mph). The pull-out was initiated by hitting the bomb-release stick on the
control column or selecting the "level flight" switch, which also retracted the
dive-brake. Brown stated, "All very sedate and totally unimpressive as a
precision weapon".
The landing procedure began at an air speed of 250 km/h (160 mph). The oil
coolers were opened fully and the radiator hatches opened to 30 degrees. At 240
km/h (150 mph) the undercarriage was lowered, which again took 30 to 40 seconds.
Flaps were lowered to their start position at 235 km/h (146 mph) and fully
deployed at 220 km/h (140 mph). The tail had to be trimmed to 4 degrees
incidence (tail heavy). Final approach was made at 200 km/h (120 mph) and
touchdown occurred at about 160 km/h (99 mph). Landing weight was roughly 13,000
kg (29,000 lb). The control column had to be held back beyond the neutral to
keep the tail wheel locked until the landing run was complete.
Role
Medium bomber
Heavy bomber
Night fighter
Reconnaissance aircraft
Manufacturer
Dornier Flugzeugwerke
Designer
Claude Dornier
First flight
4 October 1938
Introduction
1941
Retired
1945
Status
Retired
Primary user
Luftwaffe
Produced
Number built
1,925
Developed from
Dornier Do 17
Variants
Dornier Do 317
The first deliveries of Do 217s to operational units of the Luftwaffe was the
pre-production Do 217A-0 reconnaissance aircraft, which entered service with the
reconnaissance missions over the Soviet Union. Deliveries of the Do 217E started
late in 1940, with some aircraft joining another reconnaissance unit, 2 Staffel
Soviet Union from bases in Romania.
Deliveries of the Dornier Do 217J-1 started in March 1942, with night-fighter
pilots being unimpressed, considering the type to have poor manoeuvrability and
speed. The J-1 was relegated to the training role by summer that year, replaced
by the radar equipped J-2 in front-line units. Despite the aircraft's faults,
the Do 217 was widely used, being used by 11 night-fighter Gruppen, although it
did not completely equip any unit, usually being operated in conjunction with
the more popular Messerschmitt Bf 110. The Luftwaffe deployed the Do 217
night-fighter over Italy and the Eastern front as well as in direct defence of
Germany, but the type had been phased out of service by mid-1944.
Specifications (Do 217 J-2)
General characteristics
Crew: 3
Length: 18.20 m (59 ft ?8 1/2 in)
Wingspan: 19.00 m (62 ft 4 in)
Height: 5.00 m (16 ft 5 in)
Wing area: 57.00 m2 (613.54 ft2)
Empty weight: 9,350 kg (20,615 lb)
Max. takeoff weight: 13,180 kg (29,059 lb)
kW) each
Performance
Maximum speed: 487 km/h at 5,500 m (303 mph at 18,045 ft)
Range: 2,050 km (1,274 mi)
Service ceiling: 8,400 m (27,560 ft)
Armament
Guns:
about 500 rpg
Specifications (Do 217 M-1)
General characteristics
Crew: 4
Length: 17.00 m (55 ft 9 in)
Wingspan: 19.00 m (62 ft 4 in)
Height: 4.96 m (16 ft ?3 1/2 in)
Wing area: 57.00 m2 (613.54 ft2)
Empty weight: 9,100 kg (20,062 lb)
Max. takeoff weight: 16,700 kg (36,817 lb)
(1,726 hp, 1,287 kW) each
Performance
Maximum speed: 557 km/h at 5,700 m (347 mph at 18,700 ft)
Cruise speed: 400 km/h (248 mph)
Range: 2,145 km (1,332 mi)
Service ceiling: 7,370 m (24,180 ft (with max bombload))
Rate of climb: 210 m/min (688 ft/min)
Armament
Max Load 4,000 kilograms (8,800 lb) internally & externally.
Max Internal Load 3,000 kilograms (6,600 lb).
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