Minutes of the Long-Range Strategic Reconnaissance Aircraft Committee 30/09/1941
Those present:
Inspector General of Equipment General de Aero Florencio D’Parravicini
Head of the Instituto Aerotechico (Technical Research and Development) Dr. Fernando Banardos
Commander of Aerea Regimenta No 5 Capitan de Aero Enrique Molina
Commander of the Escuadrón de Reconocimiento Commando de las Fuerzas Aereas Argentinas, Flight Capitan Camilo Jimenez
D’Parravicini: Right are we ready? Then let us begin. Let me introduce Flight Capitan [Wing Leader] Camilo Jimenez, our most decorated reconnaissance pilot.
Bandardos: Were you the pilot who got those pictures back of Montevideo harbour?
Jimenez: Yes.
Bandardos: And those pictures of the aerodromes along the Grand Uruguay-Brazil border?
Jinenez: Yes Sir, that was my work too.
Molina: He has been given command of a new unit to be formed, the Escuadrón de Reconocimiento Commando de las Fuerzas Aereas Argentinas.
D’Parravicini: This unit will report directly to the Commando de las Fuerzas Aereas Argentinas [Command of the Argentine Air Forces] and will concern itself with all strategic reconnaissance operations leaving Aerea Regimenta No 5 to dedicate itself to tactical work. It is our purpose here today to select an aircraft to equip this new unit. Doctor can you give us a quick list of the proposals we’ve had?
Banardos: Certainly. the Bloch MB.178, Farman F.380, de Havilland Mosquito, Petlyakov Pe-2 and Pe-3, Junkers 88, Aero A.340, Burnelli CF-38, the Burnelli CB-14 and the SAS Ermes I. In front of you you’ll find a copy of the Instituto Aerotechico evaluation reports for each type and my department’s final assessment of the proposals on offer.
First let’s take the proposal from Société des Avions Marcel Bloch, the MB.178. The basic MB.178-CN is a two-seat night-fighter powered by two 1,479hp Gnome-Rhône 14N-20/21 14-cylinder radial engines. It has a maximum take-off weight of 7,275 kg, maximum speed 580 km/h (360 mph), range 1,800 km, a service ceiling of 11,000m (36,090 ft) and a rate of climb of 14 m/s (2,760 ft/min). The space freed by removing the two 23 mm HS.406 cannons in an upward-firing mount would allow for a couple of cameras or a third crewman. Bloch suggested fitting either Hispano-Suiza or Spartan inline engines and a bit more fuel for some extra range.
Molina: How much more range could they offer?
Jimenez: Probably not enough to meet the kind of radius of operation we desire at present. We need a radius of at least 1,300km to cover most of the likely targets within Grand Uruguay from our main base. Of course a more northern operation site could go deeper into enemy territory and flights from Paraguay could cover a large swath of land over Urugauy too.
D’Parravicini: Generally though the performance is within the acceptable range. The inline engines might make a useful increase in altitude and speed, closer to that offered by some of the other proposals.
Banardos: Internally it may be cramped to fit all that we want within it but it has some space for camera equipment.
Molina: But it might not take the three cameras we want as a minimum
Jimenez: We could add it to the shortlist. It has potential.
D’Parravicini: What is next?
Banardos: The Farman Aviation Works have offered the F.380 Foudre. It is powered by two 960hp Hispano-Suiza 12Y-32/33 liquid-cooled V12 engines, has a gross weight of 10,077 kg, maximum speed: 600 km/h (373 mph) at 8,000m (26,250 ft), cruise speed is 510 km/h (317 mph), range 2,200 km, service ceiling is 11,384 m (37,350 ft) and it takes 19 minutes to reach 8,000m. It is the only type offered here with a large pressurised cabin, it is pressurised by a 690hp Hispano-Suiza 12Xirs liquid-cooled V12 engine driving an NC-C2 supercharger. Defensive positions are mounted in dorsally, a 20mm cannon, and a single machine-gun in the nose and ventrally. 1,200kh of equipment could be carried in the former bomb-bay. The F.380 fills a similar role in the French Armee de la Air but mainly as a bomber. The F.380 has been out of production for six months now, and reported to be maintenance-intensive due to the third engine that runs the superchargers. The French would be willing to sell us factory-modified low-hour F.380s.
A subsidiary of Farman, Hanriot, is producing a simpler F.380 known as the H.250 without the pressurised cabin and powered by two 1,500hp supercharged Hispano-Suiza 12Z liquid-cooled V12 engines. Gross weight is 10,077kg, maximum speed: 630 km/h (391 mph) at 8,000m, it cruises at 510 km/h; range is 2,200 km, service ceiling 10,250m (36,909 ft) and the climb to 8,000m takes 19 minutes 7 seconds. Hanriot have offered a refined H.250 with a three-man crew with the latest HS 12Z engine trading bomb-load for more fuel.
D’Parravicini: What do you think? Would a second-hand type offer what we want?
Molina: I’m concerned over those admissions over the pressurisation system, a failure during a flight to terminate the mission early and endanger the crew. Also given the small size of the force availability is key when up to fifty percent of the force might be needed at any one time.
Jimenez: The Hanriot looks better all round to me. Given the weight savings of not having the third engine and the complex systems it seems roughly identical in all respects. Altitude is marginally lower but once you’re at cruising altitude speed is the vital factor to keep enemy interceptors behind you so they can’t catch up to you.
D’Parravicini: 30 km/h doesn’t sound much of an increase?
Jimenez: No but it might be the difference between success and failure.
Banardos: The H.250 seems the better type. I take it we can discount the F.280?
Molina: I think so; there is little advantage in that type over the other. If the French have come to some conclusion then there is little point us buying their rejects.
D’Parravicini: What is next?
Banardos: The de Havilland DH.98 Mosquito was designed as a “Speed Bomber” with no defensive armament. Surprisingly it is made wholly of wood, or to be more precise plywood veneers using a monocoque process which great structural strength for low weight and the surface finish is very smooth. The British firm is tight-lipped but we believe they are undertaking a reconnaissance development for the RAF. The specifications we were offered are for an improved Mark 2 version with two 1,280hp Rolls-Royce Merlin VI V-12 inline engines. Maximum speed is 668 km/h (415 mph), cruising speed is 523 km/h (325 mph), range with a 907kg payload is 2,888 km, service ceiling is 11,280m (37,000 ft) and the maximum take-off weight is 11,766kg.
Jimenez: A very interesting aircraft, it is the fastest bomber in Europe. It has no defensive armament so we aren’t wasting any weight and it has more range than any of the French proposals while being faster.
D’Parravicini: Would not at least some aft-facing defensive armament be wise?
Jimenez: If we were operating in a tactical regime with lower altitude in a modified medium bomber then yes it would be essential. Up high a fighter has to catch you, going at 670 km/h it will take a defending fighter some time to catch up to your height advantage and speed, in a slight dive you could outrun any serious opposition and be out of his firing range.
Banardos: FMA have looked closely at the Mosquito as a potential replacement for the Vanquish series. The layout is almost perfect; its construction is so novel for these days.
D’Parravicini: Would the wooden construction withstand long-term use? What about climatic effects?
Banardos: The skin is a sandwich, the outer layer is ply, then a middle Balsa layer, then another inner ply layer and bonded by glue and covered in dope. Over the rear fuselage the skin is wrapped diagonally, elsewhere its longitudinal and transversely laid where the stresses are less. The wing is a one-piece unit and all wood too, two box spars with laminated spruce flanges and ply webs. Spanwise spruce stringers and a ply skin is fitted along with ply compression ribs. The whole wing is glued, pinned and screwed together. The covering is Mandapolam over the plywood. It should withstand the British wet weather ok, so it should do well here. There is no reason to doubt its durability in hotter climes.
Molina: If only it had a pressure cabin too.
Jimenez: With oxygen it should be ok as it is a bit cold perhaps but certainly not a serious drawback.
Banardos: We could ask Spartan to develop one if the weight penalty wasn’t too great.
D’Parravicini: Would the British sell us such technology given the disputes over the Malvinas? I mean it all looks good on paper but would they sell us such a formidable aircraft?
Molina: Well if de Havilland have sent us a proposal?
Banardos: It is based on a converted bomber but we have heard rumours that the RAF are getting such aircraft as we speak fitted with cameras and the Merlin VI engines.
D’Parravicini: Much to think on. What is next?
Banardos: The Petlyakov Pe-2 is licence-built in Chile as the ENAER B1E-1 Caracara. We discounted it owing to insufficient ceiling, range and generally it would more suited to tactical reconnaissance. It’s worth noting that the Chileans use the 1,300hp FMA-Spartan 12V-1300S and now that FMA is producing the 1,500hp 12V-1500S and SS some improvement to its already good speed is likely. Junkers offered a very thin proposal based on the Junkers Ju-88. The range of 3,040 km with full fuel load is good but the speed and ceiling and rate of climb are far too low compared to the other types on offer and so Instituto Aerotechico reject this proposal too.
Jimenez: I would concur with that assessment. Certainly they offer nothing near the Mosquito or MB.178.
Banardos: The Instituto Aerotechico approached the Czechoslovak manufacturer Aero about its new two-seat twin-engined fighter-bomber, the Aero A.340. It has a mid-set monoplane and twin tailfins and the engine nacelles are designed to minimise drag. The first prototype flew in May 1941 with the second prototype to following in November 1940. Service entry with the Czech Air Force is expected during late 1942. The engines are 1,450hp Minerva-Avia 105 V-12s. Loaded weight is 9,450 kg, maximum speed: 528 km/h (330 mph) at 6,000 m (22,960 ft), cruise speed is 480 km/h, range 2,000 km, service ceiling: 10,500 m (34,500 ft), rate of climb: 545 m/min and a climb to 6,000m would take 11 minutes. Armament comprises a dorsal machine-gun and wing-root cannon and nose machine-guns. Aft of the cockpit is a large enough bay for two overlapping vertical cameras.
D’Parravicini: A good mix of performance, the speed is a little lower than I’d like though. Generally as a conversion from a fighter it lacks the full internal space but it certainly could meet a minimum 1,000 km radius.
Jimenez: I’d replace the cannon with more fuel, but I agree it has potential, perhaps less than the MB.178. Tactically it would make a great medium-level reconnaissance type. Myself I’m not too keen for the task in hand. The other offers look more tempting overall.
Banardos: Burnelli made a proposal using the CF-38 Skipray fighter. This twin-engined two-seat fighter is powered by two 1,750hp Orenda Oneida II V-12 inline engines, loaded weight it 7,937kg, maximum speed 685 km/h (426 mph), range is 1,622 km, service ceiling 12,466m (40,900 ft) and rate of climb is 18.2 m per second. It has a 2,000lb payload. The CB-14 was also proposed but fell short of the requirements.
D’Parravicini: The CF-38 looks even better than the Mosquito on paper. Certainly it’s a world beater given its reputation at the Talons events over the last couple of years.
Molina: Yes but it a fighter, not a bomber, you still need to find somewhere to put those cameras. The disposable load looks good, remove the 20mm cannon and it would have the weight to carry all we need. Defensively it could tackle any likely interceptor.
Jimenez: The range is far too low though. None of these proposals have met the entire 3,000 km range requirement but this is too low.
D’Parravicini: I remember reading in a journal that the Orenda Oneida was based on the Rolls-Royce Griffon. I wonder if we put the latter into the Mosquito what would we get then?
Molina: The General has a point, the altitude performance is good.
Jimenez: Looking at this graph 595 km/h at 8,000m is better than the French aircraft.
Banardos: The massive wing could probably hold more fuel to meet some of the requirement.
Jimenez: The next proposal looks interesting.
Banardos: The final proposal came from Italy and is the SAS Ermes I. It has been designed by a team of mostly ex-Savoia-Marchetti and ex-Macchi staff, with technical knowledge on pressurised aircraft coming from the Piaggio. If we purchased this type Italy has offered work on the autopilot to FMA subsidiary Fabrica de Instrumentos for a Sperry-type autopilot in order to reduce the workload on the crew. We received an initial sketch of the Ermes; it is powered by two Isotta-Fraschini diesel engines and is a twin-fuselage design. The pressure-cabin holds a crew of two. Range is excessive for our needs but with further discussions with SAS they can tailor the design to our needs with future potential for range growth. Maximum speed is around 692 km/h (430 mph). It is designed to cruise at 10,600m and given the low wing loading it should be able to out-turn a fighter but its speed along would give a large measure of protection from interceptors given the time they would need to climb and chase. It could easily carry 1,000kg of equipment too.
Molina: Are these projected ranges realistic?
Banardos: We have asked SAS to cut the range but it still exceeds what we require as a minimum. Even if some of the maths is off at this early design stage there is ample fuel. We concur with the general estimates.
D’Parravicini: I thought Britain and Germany led the world in aero diesel engine technology but these seem to be very fine engines. We need to find out more about the advantages of diesel engines.
Molina: Well it’s an unusual aircraft.
Jimenez: But it’s the only one designed for the same specific task as we have in mind. It has excellent performance, the same level as the CF-38 but with much superior altitude and range. It has a pressure cabin too; in fact you could argue this is the F.380 crossed with the Mosquito and CF-38. It fulfils all the requirements, even if the proposal is a bit sketchy at this early stage its promising work.
Banardos: And it offers us some offset work too.
D’Parravicini: Given this is a paper plane and the others are flying today what kind of penalty would it incur to wait for such an aircraft?
Banardos: We might not get any until 1943. Maybe 44.
D’Parravicini: And the radical layout? A wooden wonder is one thing but a huge twin-fuselage aircraft like this is something else. Ground handling issues must be tackled too.
Banardos: FMA and ENAER worked on such a proposal for a long-range fighter using two Pulqui fuselages. We have considerable date of our own to work on. The Instituto Aerotechico sees no risks in the design other than the pressure cabin and engines.
Jimenez: Seeing as those Isotta-Fraschini diesel engines are being used on commercial flights now I see no serious development problems to halt the programme. My vote goes for this aircraft.
Molina: For me the Mosquito is the better option. We can have it now.
D’Parravicini: Maybe we should recap. Bloch MB.178 possible with inlines but far short of range, Farman F.380 rejected, Hanriot H.250 acceptable but still flawed, de Havilland Mosquito gets a thumbs up from everyone, Petlyakov Pe-2 and Pe-3 rejected, Junkers 88 rejected, Aero A.240 rejected, Burnelli CF-38 like the MB.178 offers some excellent performance but is short on range, the Burnelli UB-14 is rejected and the SAS Ermes gets approval, meets all the requirements but it’s the risky choice. So what is the plan of action? Doctor which would you go for?
Banardos: The Ermes. We could fill the gap with another type until it is ready. Looking forwards into the latter 40s it should still be an effective platform, more so than the other converted bombers offered here.
Molina: Mosquito. If we can get them.
Banardos: Perhaps if FMA does build a similar bomber type we could use that instead? It might take longer but as a tactical type it would outshine anything else and is capable of strategic use.
D’Parravicini: Well I would go for the Mosquito too, or the CF-38 if it could grow to accommodate more range. Who would we guarantee FMA could develop such a bomber though?
Banardos: Well the British might not object to us ordering one, maybe two standard Mark 2 bombers. We could fit them ourselves as reconnaissance aircraft or we could give them to FMA to strip down and copy. An enlarged version with the newest Spartan 12V-1500 engines would be even better.
Jimenez: But they come nowhere near the Ermes. As a stand-in I’d go for the Mosquito. Surely a deal could be done for six?
D’Parravicini: If we are in agreement then we should recommend to the Staff that the SAS Ermes I be procured as a joint development with Italy to fulfil the requirement and that six Mosquitos be obtained from de Havilland for reconnaissance until the Ermes is ready and also that FMA should be able to study the type to refine its ideas for the I.Ae.24 tactical bomber and reconnaissance aircraft. We recommend the latter variant as a tactical/ strategic type to back up the Ermes.
Molina: I agree.
Jimenez: I concur Sir.
Banardos: I would agree with that General.
D’Parravicini: Very well lets adjourn and go to lunch.