Henschel was one of
four companies (the others being Focke-Wulf, Gotha and Hamburger
Flugzeugbau) to which, in April 1937, the Technische Amt of the
Reichsluftfahrtministerium (RLM) issued a specification for a
twin-engine ground-attack aircraft. It was required to carry at least
two 20 mm MG FP cannon and to have extensive armour plating protection
for crew and engines. The two designs for which development contracts
were awarded on 1 October 1937 were the Focke-Wulf Fw 189C and Henschel
Hs 129. The latter was another Friedrich Nicolaus design with a light
alloy stressed-skin fuselage of triangular section. It contained a
small cockpit with a restricted view, necessitating the removal of some
instruments to the inboard sides of the engine cowlings. The windscreen
was made of 75 mm (2.95 in) armoured glass and the nose section was
manufactured from armour plating. Nose armament comprised two 20 mm MG
FF cannon and two 7.92 mm (0.31 in) MG 17 machine guns. The prototype
flew in the spring of 1939, powered by two 465 hp (347 kW) Argus As
410A-1 engines, and two further prototypes were flown competitively
against the modified Fw 189 development aircraft for the Fw 189C.
A Henschel Hs 129B-3/Wa of 14.(Pz)/Sch.G 9 fitted with the 75 mm BK 7,5
(PaK 40L) anti-tank gun in the winter of 1944-45
Although the Henschel
aircraft was considered to be underpowered and sluggish, and to have
too small a cockpit, the company was awarded a contract for eight
pre-production Hs 129A-0 aircraft, and these were issued initially to 5
(Schlacht)./LG 2 in 1940, but transferred to 4./SG 101 at Paris-Orly in
1941, with the exception of two which were converted at Schonefeld to
accept Gnome-Rhone 14M 4/5 radial engines. It was with this powerplant
that 10 Hs 129B-0 development aircraft were delivered from December
1941; improvements included a revised cockpit canopy and the
introduction of electrically-actuated trim tabs, and armament comprised
two 20 mm MG 151/20 cannon and two 7.92 mm (0.31 in) MG 17 machine
guns. The production Hs 192B-1 series went into service first with 4./SchG
1 at Lippstadt in April 1942 and also became operational on the Eastern
front, where the type was to be used most widely, although it served
also in North North Africa, Italy and in France after the D-Day
landings. Sub-variants of the M 129B-1 series included the Hs 129B-1/R1
with additional offensive armament in the form of two 110 lbs (50 kg)
bombs or 96 anti-personnel bombs; the Hs 129B-1/R2 with a 30-mm MK 101
cannon beneath the fuselage; the Hs 129B-1/R3 with four extra MG 17
machine-guns; the Hs 129B-1/R4 with an ability to carry one 551 lbs
(250 kg) bomb instead of the Hs 129B-1/R1's bombload; and the Hs
129B-1/R5 which incorporated an Rb 50/30 camera installation for
reconnaissance duties.
By the end of 1942 the
growing capability of Soviet tank battalions made it essential to
develop a version of the Hs 129 with greater fire-power, leading to the
Hs 129B-2 series which was introduced into service in the early part of
1943. They included the Hs 129B-2/Rl which carried two 20 mm MG 151/20
cannon and two 13 mm (0.51 in) machine-guns; the generally similar Hs
129B-2/R2 introduced an additional 30 mm MK 103 cannon beneath the
fuselage; the Hs 129B-2/R3 had the two MG 13s deleted but was equipped
with a 37 mm BK 3,7 gun; and the Hs 129B-2/R4 carried a 75 mm (2.95 in)
PaK 40L ('L' for Luftwaffe) gun in an underfuselage pod. Final
production variant was the Hs 129B-3 of which approximately 25 were
built and which, developed from the Hs 129B-2/R4, substituted an
electro-pneumatically operated 75 mm BK 7,5 gun for the PaK 40 (Panzer
Abwehr Kanone 40). The lethal capability of the Hs 129B-2/R2 was
amply demonstrated in the summer of 1943 during Operation 'Citadel',
the German offensive which was intended to regain for them the
initiative on the Eastern Front after the defeat at Stalingrad. During
this operation some 37,421 sorties were flown, at the end of which the
Luftwaffe claimed the destruction of 1,100 tanks. However accurate
these figures, not all of those destroyed could be credited to Hs 129s,
but there is little doubt that the 879 of these aircraft that were
built (including prototypes) played a significant role on the Eastern
front. In spite of its small numbers and deficiencies, proved extremely
successful in the anti-role, however, it suffered heavy losses and not
many examples survived the war.
The Hs 129B equipped
three Staffeln of the 8th Assault Wing of the Royal Romanian Air
Corps. On 23 August 1944 there was a coup in Romania, as a result of
which the country changed from being an ally of Germany to becoming an
enemy. These Hs 129Bs, accordingly were used against the German armies,
finally being combined into a unit equipped with the Ju 87D Stuka.
In late September 1944,
the entire manufacturing programme was abandoned, along with virtually
all other German aircraft production except the 'emergency fighter
programme'. Total production had amounted to only 879, including
prototypes. Because of attrition and other problems, the Hs 129 was
never able to fully equip the giant anti-tank force that could be seen
to be needed as early as winter 1941-42, an overall effect on the war
was not great. Towards the end, in autumn 1944, operations began to be
further restricted by shortage of high octane petrol, and by the final
collapse of Germany only a handful of these aircraft remained.
The Cockpit
Because of the
triangular-section fuselage and the need to keep the airframe as small
as possible the cockpit of the Hs 129 was very cramped. So cramped in
fact that the Revi C 12/C gunset was mounted on the aircraft nose
outside of the cockpit and certain engine instruments were mounted on
the inboard side of the engine nacelles for the pilot to view. The
entire nose section formed a welded armoured shell 6 mm to 12 mm thick
around the pilot, with toughened 75 mm thick glass in the canopy. The
total weight of the nose armour was 2,380 lbs (1080 kg). A large pilot
would have a great deal of trouble in handing the aircraft in ground
attacks and a short control stick required a great deal of strength to
move even in the modest manoeuvres.
New Weapons
The massive build-up in
Soviet armour strength with thick-skinned tanks contrasted with the
faltering strength of the Sch.G. units, which continued to be afflicted
by poor engine reliability despite the addition of properly designed
air filters. The overriding need was for more powerful anti-armour
weapons, and on 10 January 1944 a special unit, Erprobungskommando
26, was formed at Udetfeld out of previous Sch.G. units to
centralise the desperate effort to devise new weapons and tactics. Its
Hs 129s soon appeared with various new armament, some of which were too
much for what was, after all, a small aircraft.
The outstanding example
of the new weapons was the radically different Forstersonde SG
113A. This comprised a giant tube resembling a ship's funnel in the
centre fuselage just behind the fuselage tank. Inside this were fitted
six smooth-bore tubes, each 1.6 m (5 ft 3 in) long and of 77 mm
calibre. The tubes were arranged to fire down and slightly to the rear,
and were triggered as a single group by a photocell sensitive to the
passage of a tank close beneath. Inside each tube was a combined device
consisting of a 45 mm armour piercing shell (with a small
high-explosive charge) pointing downwards and a heavy steel cylinder of
full calibre pointing upwards. Between the two was the propellant
charge, with a weak tie-link down the centre to joint the parts
together. When the SG 113A was fired, the shells were driven down by
their driving sabots at high velocity, while the steel slugs were fired
out of the top of each tube to cancel the recoil. Unfortunately, trials
at Tarnewitz Waffenprufplatz showed that the photocell system often
failed to pick out correct targets.
Another impressive
weapon was the huge PaK 40 anti-tank gun of 75 mm calibre. This gun
weighed 3,303 lbs (1500 kg) in its original ground-based form, and
fired a 7 lbs (3.2 kg) tungsten-carbide cored projectile at 3,060
ft/sec (933 m/sec). Even at a range of 3,280 ft (1000 m), the shell
could penetrate 5 1/4 inches (133 mm) of armour if it hit square-on.
Modified as the PaK 40L, the gun had a much bigger muzzle brake to
reduce recoil and electro-pneumatic operation to feed successive shells
automatically. Installed in the Hs 129B-3/Wa, the giant gun was
provided with 26 rounds which could be fired at the cyclic rate of 40
rounds per minute, so that three or four could be fired on a single
pass. Almost always, a single good hit would destroy a tank, even from
head-on. The main problem was that the PaK 40L was too powerful a gun
for the aircraft. Quite apart from the severe muzzle blast and recoil,
the sheer weight of the gun made the 129B-3/Wa almost unmanageable, and
in an emergency the pilot could sever the gun's attachments and let it
drop.
Specifications (Henschel
Hs 129B-2/R2)
Type: Single
Seat Close Support & Ground Attack
Design: Chief
Engineer Friedrich Nicolaus of Henschel Flugzeugwerke AG
Manufacturer:
Henschel Flugzeugwerke AG
Powerplant:
(B-Series) Two 700 hp (522 kW) Gnome-Rhone 14M 4/5 14-cylinder radial
piston engines rated at take-off. (A-Series) Two 465 hp (347 kW) Argus
As 410A-1 air cooled inverted Vee 12-cylinder engines.
Performance:
Maximum speed 253 mph (407 km/h) at 12,565 ft (3830 m); service ceiling
29,525 ft (9000 m); initial climb rate of 1,600 ft (486 m) per minute.
Fuel: Two
self-sealing wing tanks each holding 45 Imperial gallons (205 litres)
and a single self-sealing fuselage tank of 44 Imperial gallons (200
litres). The Hs 129B-2 was capable of carrying a single droppable
auxiliary fuel tank of 33 Imperial gallons (150 litres)
Range: (Hs
129B-2) 427 miles (688 km) on internal fuel. (Hs 129B-1) Range 348
miles (560 km) on internal fuel.
Weight: Empty
equipped 8,400 lbs (3810 kg) with a maximum take-off weight of 11,574
lbs (5250 kg).
Dimensions: Span
46 ft 7 in (14.20 m); length 31 ft 113/4 in (9.75 m); height 10 ft 8 in
(3.25 m); wing area 312.16 sq ft (29.00 sq m).
Armament: (B-1
Standard) Two 20 mm MG 151/20 cannon with 125 rounds per gun and two
7.92 mm (0.31 in) MG 17 machine guns with 500 rounds per gun. (B-2
Standard) Two 20 mm MG 151/20 cannon with 125 rounds per gun and two 13
mm (0.51 in) MG 131 machine-guns with 250 rounds per gun (although some
aircraft retained the 7.92 mm (0.31 in) MG 17 machine guns). All the B
Series aircraft were capable of using Rustsätze Kits which increased
the aircraft's ordnance capacity. See the individual variants for
specific information.
Variants: Hs
129A-0, Hs 129B-0, Hs 129B Series, Hs 129B-2 Series, Hs 129B-2/Wa (Waffentrager),
Hs 129B-3/Wa (Waffentrager), Hs 129C.
Avionics: Revi C
12/C gunset.
History: First
flight (Hs 129V-1) early 1939, service delivery (Hs 129A-0) early 1941,
first flight (Hs 129B) October 1941, service delivery (Hs 129B) late
1942.
Operators:
Germany (Luftwaffe), Hungary, Romania. |