PAH-2: alternatives to and evolution of the Tiger attack helicopter

New PAH II entry: VFW Fokker/Westland Helicopters P277

One of the large surprises air show 1977 in Le Bourget/Paris was common the model debut from VFW Fokker and Westland of the Helicopters and in all silence of developed combat helicopter P 277 'Fleidermaus' (Bat). With this sample it concerns a project suggestion on the fulfilment of the tactical demand of the Federal Republic of Germany on a helicopter laid out for antitank defense. Certainly thereby the development of the PAH II steps into a completely new phase.

In May/June 1977 became known the procurement of 212 machines of the antitank defense helicopter of the 1. Generation (PAH I) green light gives. With this sample it acts around a derivative out of the Bo 105M, by which for February 1976 two machines are extensively tested. Numerous studies resulted in that with appropriate weapons of equipped Bo 105M can fulfill the demands on the PAH 1. In addition also attempts with an inserted mg 3 belonged in swiveling carriage and a sechsläufigen mini act of Emerson Electric at the fuselage lower side. Also the usefulness of the 20-mm cannon RH 202 of Rhine metal was examined.



Although all of this led to excellent results, one decided in the long run for the equipment of the PAH I with six antitank defense missiles of the German of French type HOT (High Optical tube) in three-foldwho far from. These 260 m/s fast and 32 kg heavy weapon equipped with folding wings an employment use of 75 to 4000 M. with six HOT armed Bo 105P has comes including the complete visor equipment on a takeoff weight of 2400 kg. With the PAH I the army aviators are finite starting from at the end of of 1979 in case of an armed conflict able to be able to fight solid tank break-throughs more effectively than ever before. Everyone of the three corps will receive additionally an antitank defense regiment (PAR) with 56 Bo 105P.

But back to the antitank defense helicopter of the 2. Generation, whose development with the decision stepped over the troop introduction of the PAH I into a new concrete phase. To the principal claims of the German army aviators to the new sample belong not only more efficient weapons, but above all the night operations and bad weather fitness. Only well-known forerunner for the new PAH system, which was to be realized to European joint venture work and be introduced in the second half of the eighties, was to June 1977 the draft Bo 115 prepared by MBB. It was not amazing thus that the project of the P developed together by VFW Fokker and Westland knocked 277 into Le Bourget themselves with numerous specialists like a bomb.

Both companies worked in the last two years and in all silence on the draft of the new combat helicopter, which in the weight class around 4500 kg ranked and outwardly a little reminds of the American sample Bell Huey Cobra. Not only from time, but in particular from cost reasons one already took Westland as a basis Lynx, which fulfills the operational demands of the PAH II fully in the initial phase the complete dynamic system of the light multi-purpose helicopter.

The power plant of the P 277 consists of two 960-WPS-Turbinen of the type of Rolls-Royce IN ACCORDANCE WITH 4, which make a maximum speed of 290 km/h and a maximum rate of climb of 13,4 m/s at ground level for it possible. This also shaft turbine marked with RB.360 worked satisfactorily until today with the Lynx outstanding. It is characterized by a small fuel consumption and is very fast-reacting. The rotor system of the P 277 consists as with the Lynx of a hingeless four-sheet main rotor with a diameter of 12,80 m and a likewise four-leaf tail rotor, whose diameter is with 2,21 m.

For the security of the calculated flight performances served VFW Fokker a P 277-Modell, which was examined in the context of a 75stündigen of program and in the most diverse configurations in the wind tunnel. In addition among other things also the influence of the cannon and the Visiereinrichtung belonged apart from the trunk base data and the pressure distribution around the front and middle trunk. The unloaded weight of the P 277 is with 2460 kg and the maximum takeoff weight with 4760 kg.

The two master units of the tail landing gear chassis are retractable into lateral trunk cars. As is the case for some other helicopter samples the zweiköpfige crew is easily graduated accommodated in a tandem cockpit. Both seats are armored like all vital systems of the equipment and engine installation.

As tasks of main employment of the P 277 the fight of armored ground targets as well as the battlefield support are considered with solid tank break-throughs. Beyond that it is to be in addition, able to suppress opposing soil fire and to accompany and protect if necessary heavy transport helicopters with their employments. For all these tasks the P can carry 277 different weapons of the most modern conception, to which beside, to a fuselage-side 20-mm cannon with 250 in particular two four-fold throwers for HOT or TOW missiles belong to shot. For low attacks however also two throwers with 38 2.75 can " instead of its - rockets and for armed escort-in-corrode two air-to-air guided weapons Matra 550 or Redeye to be carried.

All this, the proven dynamic system of the Lynx as well as a durable cell and equipment with small maintenance need, make the P 277 a combat helicopter with high readiness of application. It corresponds not only to the tactical demands of the army aviators for the PAH II, but also the political conceptions as international community project. Because of the mentioned assumption of the Lynx Rotorsystems and the associated Verkürzung of development time and - the P 277 costs at the beginning of the eighties of the troop with its realization be supplied around half could. The combat helicopter P 277 represents without any doubt a further contribution to the standardization of weapons and equipment within NATO.

Beyond that the development of a modern PAH, on which also the Aerospatiale (France) and Agusta (Italy) work, was completely again animated by the debut of the P 277. One should further pursue it in the next years with largest interest.

The airmobileness of the army will be again crucially improved by the PAH II - it is now the Bo 115 or the P 277 -. The arsenal of the army for the effective fight of armored vehicles will be considerable in the eighties. It is enough then from the Panzerfaust over guided missiles of different ranges up to own hunt and battle tanks as well as with appropriate weapons to equipped combat helicopters of most modern conception. Hans's Redemann

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The helicopter scene of the aero salon of this year was clearly characterized by the model debut of a new combat helicopter, which VFW Fokker as well as Westland Helicopters developed in the last two years in all silence. The new helicopter with the designation P.277 bat corresponds to a large extent to the tactical demands of the German Federal Armed Forces for the PAH II. it resembles outwardly the American Bell AH-1 Hueycobra and ranks in the weight class by 4000 kg. As power plant as with the Lynx two 900 WPS turbines of the type Rolls-Royces RB.360 are intended. In addition one took over the entire rotor system of the Lynx, which a crucial contribution might be for standardization within NATO. Beyond that this would reduce the expenditure at costs and time for the development of the new helicopter to half.

With a realization of the all-weather suited P.277 this could take up for instance in the middle of the eighties its active troop service with the German army aviators. As its primary Einsatzaufgaben are considered the battlefield support with solid tank break-throughs, the purposeful fight of other armored ground targets and the escort of heavy transport helicopters. With a flying weight by 4200 kg and with eight HOT guided weapons the P.277 nearly 290 km/h is equipped to be fast. In addition it can be armed with a rotating turret at the fuselage lower side with 20 a mm cannon with 250 shot. One may be strained on the further development of the PAH II, which was again animated by the appearance of the P.277.

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• Air International, August 1977

TinWing said:

I wonder if it would have been neccessary to redesign the Lynx's gearbox? Typically, this is the sticking point in obtaining design commonality between attack and transport type helicopters.

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Europe's 1980s tank-busting helicopter

ONE of the relatively few genuine military surprises at the Paris Show was the announcement by Westland and VFW-Fokker that they are collaborating on an attack helicopter for central European use in the late 1980s. They are working to a requirement, not yet officially confirmed by the West German Army, generally known as PAH-2 (Panzer Abwehr Hubschrauber) and calling for a specialised day/night anti-armour helicopter of medium weight. It would initially complement and then probably replace the lighter, Hot-armed BO105M PAH-1, the first of which is due for delivery in 1979.

Westland and VFW-Fokker are not alone in bidding for PAH-2. Aerospatiale and MBB—which have been working together, particularly on rotor design, for ten years—are also collaborating but have not been as quick off the mark in announcing details of a firm project. In fact, the Franco-German partners seem much less sure of the scope of their collaboration or of such details as worksharing and technology level.

Aerospatiale, already linked with Westland on the Lynx but informed of the relationship with VFW only at a late stage, remains outwardly unconcerned by the new Anglo-German arrangement. The French company believes that the German and French Armies are harmonising their antitank helicopter requirements for the late 1980s, and that PAH-2 will therefore turn into a Franco-German project along the lines of Alpha Jet or the Euromissile weapons.

Helicopter division director Francois Legrand tells Flight that it is too early to say that either a programme leader or a dynamic system on which to base a PAH-2 has been decided between Aerospatiale and MBB. The German company, on the other hand, appears confident that it will lead and that a scaled-up BO105 system will be used. Legrand believes that a new airframe, new engines, new dynamics and new weapon systems are all feasible, in spite of the resulting extra cost and time. Westland and VFW have in the meantime come up with a firm proposal, designated P.277, which is based on major Lynx assemblies already in production and said to meet fully PAH-2 response and performance requirements at projected mission weights. Bearing in mind the cancelled French Army anti-tank variant and the British Army's planned roles for the utility version, the companies have a safe bet in claiming that the Lynx already meets anti-tank helicopter requirements. It was this, they say, which led to the adoption and development of the VFW-Fokker, which is responsible for P.277 fuselage design, has built a full-scale mock-up in Germany of the hingeless rotor, low-profile transmission and highly responsive engines.

The partners are also promoting the idea that, with Lynx now almost fully developed and adopted as a Nato project, use of Lynx assemblies for PAH-2 would keep development cost to just over half that of a completely new helicopter and reduce development time. A large measure of commonality with other Lynxes in the Nato fleet would be an additional bonus.

The companies say that they could fly three prototypes within about three years of a firm go-ahead, delivering the first production aircraft at the end of the fifth year. Production deliveries of a completely new design would begin an estimated seven years from go-ahead, by contrast.

P.277 performance projections are based on the use of two Rolls-Royce Gem-4 engines. At the maximum allup weight of 4,300kg and carrying eight Hot missiles, the P.277 would have a maximum continuous cruise speed of 150kt TAS with an outside air temperature of 20°C. At an AUW of 3,875kg with the same number of missiles and an OAT of 10° C, the continuous speed is 160kt. At 3,625kg and 10°C, again with eight missiles, the P.277 could achieve a 5min dash speed of 167kt TAS. Sea-level vertical rate of climb (at a 5min take-off power rating) would vary between 4,000ft/min at 3,625kg and 2,700ft/min at 4,300kg (both at an OAT of 10°C). Maximum forward rate of climb under the same conditions would be between 3,450ft/min and 2,650ft/min. Single-engine rate of climb with a 1 hr contingency rating, again at 10°C, would be very nearly 1,500ft/min at 3,625kg and just under 1,000ft/min at 4,300kg.

Three kinds of mission are being projected by Westland and VFW for the P.277: anti-tank, armed escort and ground attack. For the first of these, a 140km sortie has been sketched out, carrying eight anti-tank missiles and 250 rounds of 20mm ammunition. The profile includes a 110km transit out and return at 150kt, 30km of nap-of-the-earth flying in the battle area at 70kt, 20min of loiter and attack, and 40min hovering time left over, plus reserves.

A typical armed-escort mission, with two Matra Magic air-to-air missiles, eight Redeyes and 2,000 rounds of 7.62mm ammunition, could have a radius of action of between 250km and 300km. It would be flown mostly at 120kt, but with 150kt dashes, a couple of attacks and 20min of hovering and/or loiter.

P.277 is already well defined, after 75hr of tunnel tests covering some 700 different configurations. This work has been directed at predicting the performance effects of the canopy form, chin sight, under-fuselage cannon and various other weapon installations. German Government approval of the PAH-2 requirement is still some way off and will depend largely on funding priorities to be settled at the end of this decade. After that, the choice between the Westland/VFW and Aerospatiale/MBB proposals will also depend to an extent on the requirements of other European armies.

This may prove to be crucial, since a collaborative programme is unlikely to get under way without both countries' armies agreeing on the requirement and purchasing a number of aircraft. The British Army has always shied away from specialist anti-tank helicopters, preferring to use multipurpose machines such as the Lynx or the smaller Gazelle. The French Army, however, has the longest antitank helicopter history of all, and the present signs of renewed interest in an aircraft dedicated to the role may give a potent competitive edge to the eventual MBB/Aerospatiale submission for PAH-2.

P.277 DATA
Fuselage length 13.1m
Fuselage width 1.1m
Fuselage height 2.5m
Overall height 3.5m
Main rotor diameter 12.8m
Tail-rotor diameter 2.2m
Empty weight 2,464kg
Typical night-equipped basic weight 2,998kg
Typical operating weight (with 8 Hot/Tow, 20mm cannon plus 250 rounds) 3,749kg
Max mission take-off weight 4,309kg
Max permitted gross take-off weight 4,763kg
Internal fuel capacity 740kg
Equipment Communications: intercom, UHF, VHF, HF, secure speech .
Navigation: Doppler, radar height, UHF homing, Tacan, IFF/SIF
Flight control: stabilisation in pitch, roll and yaw; heading, radar height and barometric height holds
Target sighting: dual-magnification optics with IR tracker. Compatible with FLIR or laser tracking sensors, lase, rangefinder, helmet sights, night vision/sighting systems and lase, weapon-training simulator

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Militaryphotos.net

www.militaryphotos.net

High-resolution vulnerability

The vulnerability of the helicopter depends on the engaging ammunition type, the impact point and often the distance. The two pods on the helicopter prevent blind spots and provide a realistic target signature. The impact areas and the vulnerability of each area are customisable and platform-unique. Different vulnerability models can be downloaded to the generic system dependent on the helicopter type. The target system calculates the effect of incoming fire and informs the crew accordingly. Opposing forces experience rotary-winged aircraft vulnerability to incoming fire through visual effects on the target system. The results of training are stored in the system for use during after-action reviews (AARs). If the system is instrumented, online monitoring and vulnerability to area weapons are included.

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robunos said:

Is it just me, or does the PAH-2 concept posted at
the top of this page, and on the first page, look like
an Agusta A.129 with a fenestron?

cheers,
Robin.

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Jemiba, wasn't implying any kind of commonality of design, but to the
uninitiated.....




cheers,
Robin.

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James said:

Thanks for sharing luedo. Not the best looking chopper ever (imo) but certainly looks like it could have done the job.

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luedo34 said:

Well, being honest, this bird is as ugly as hell!

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richard said:

And from an old Flugrevue ( please ,don't ask me the year , I don't know ... )
a missing link in the way from Bo115 to PAH2 . There was no text ,only the drawing ...

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