|HFB 320 Hansa Jet|
Exhibited Hansa Jet
April 21, 1964
1966 to 1973
|Number of pieces:||
The HFB 320 Hansa Jet is a twin- engine business jet made by Hamburger Flugzeugbau GmbH in the 1960s. In addition to two prototypes, 45 series copies were made. It was the first series-produced civil aircraft with jet propulsion in Germany.
After the re-approval of aircraft construction in Germany and the start of aircraft production, primarily with the license production of military aircraft ( Noratlas , F-104 ), the German aviation industry tried to regain a foothold in civil aviation. In 1960, the Hamburger Flugzeugbau (HFB) proposed the HFB 314 project to the Federal Ministry of Economics - a twin-engine short- and medium-haul aircraft for 80 passengers. The project was not supported by the Federal Ministry of Economics as it would have been in competition with the Caravelle of the French aircraft factory Sud Aviation.
A second proposal for the development of a twin-engine business jet in 1961, however, found support from the Federal Ministry of Economics. The HFB 320 project was funded with a total of around DM 150 million, of which, however, around DM 100 million was repaid. The HFB had the entire program responsibility as well as the development and production engineering. In addition, the fuselage and vertical stabilizer structure was manufactured at the Finkenwerder plant and all structural parts were equipped, as well as final assembly and the approach.
The following companies were involved:
- Siebel AG , Donauwörth (wings)
- CASA , Madrid (tailplane)
- GE Boston-Lynn (engines)
- Lockheed (Automotive Products), Liverpool (chassis)
- Saurer , Switzerland ( APU )
- Lucas Industries , Luton (front windows)
- Normalair , England (air conditioning, pressure and oxygen system)
The first flight of the HFB 320 took place on April 21, 1964. As part of the flight test one of the prototypes (crashed aircraft marks D-CHFB ) on May 12, 1965 not far from Torrejón de Ardoz in Spain in case of drawing tests from (so-called "anti-stall attempts."; See also stall ). During this flight test, the HFB 320 went into a flat spin and with it the horizontal stabilizer of the T-tail unit in an area shielded from the current. The elevator was then ineffective and the flat spin could no longer be ended. As a last resort, the pilots deployed the braking parachute, but this was ineffective. The test pilot Loren Davis was killed. The other test pilot Hans Bardill and another crew member were able to save themselves with the parachute (see also flight accident of an HFB 320 Hansa Jet near Madrid ) .
The first production aircraft (D-CARA) had its maiden flight on February 2, 1966. The approval by the Luftfahrt-Bundesamt was granted on February 20, 1967, the FAA followed on April 7, 1967. The approval was carried out according to the Civil Air Regulation 4b (CAR 4b) provisions. The selling price at the time was around three million DM.
In addition to the prototypes V1 and V2, the following HFB-320 aircraft were built and sold:
- S1: additionally for flight tests, later use at DLR
- S2: additionally for flight testing
- S3-S37: sold in Europe, USA, Mexico and South America. Period from 1967 to 1972.
- S38-S45: HFB 320 ECM, ordered by the BMvg and delivered to JaboG 32 in the period from 1976 to 1982.
In 1969, the Hamburger Flugzeugbau GmbH was taken over by Messerschmitt-Bölkow-Blohm (MBB). MBB marketed the HFB 320, but was only able to sell 45 machines of this type, 16 of them to the Bundeswehr . These were used in flight readiness in Cologne-Wahn and at the test center 61 (today: Wehrtechnische Dienststelle 61 ) in Manching. From 1976 eight appropriately modified machines (HFB 320 ECM) served as a trainer for electronic warfare at JaboG 32 in Lagerlechfeld until they were decommissioned in 1994 (one machine crashed after colliding with a fighter plane in 1976) .
Probably the last flight of an HFB 320 took place on November 30, 2004. An HFB 320 of the US airline Grand Aire Express ( N604GA ) was to be transferred from Chesterfield near St. Louis to Toledo (Ohio) . Shortly after taking off from Spirit of St. Louis Airport in Chesterfield, the plane crashed into the Missouri River , killing both pilots. The cause was a maintenance error, the contributing cause was bad weather.
Although the HFB 320 was not an economic success, it nonetheless (together with the VFW 614 and C-160 ) formed the basis for a whole generation of engineers, technicians and skilled workers to later play a decisive role in shaping the successful Airbus program.
The machine, designed as a mid-decker , has a T-tail unit and two engines attached to the rear of the fuselage. The special feature of this type are the wings with a negative sweep (pre- sweep ) of 15 °. This constructive design was based on knowledge that Baade and Wocke had already gained at Junkers with the Ju 287 . Due to the negative arrow, it was possible to arrange the wing spar connectors behind the cabin, which benefited the space available. This allowed for maximum headroom and in 1963 was a competitive advantage over the competing Learjet 23 , Jet Commander and Hawker Siddeley HS.125 models . A disadvantage of the negative sweep, however, was a positive aeroelastic twisting of the wing when the angle of attack was increased, which at high angles of attack could lead to an earlier flow separation in the outer wing area. In order to reduce the positive aeroelastic twist, the wings had to be made very rigid (conically rolled upper and lower shells with a thickness of 2-4 mm). Additional tanks were also attached to the wing tips to further reduce positive twist. The wings themselves were equipped with ailerons, inner slats, double-gap landing flaps (max. 50 °) and airbrakes.
The wing structure consists of three sections (nose boxes, wing center box and end boxes). The wing center box is designed as a torsion box and also serves as a wing tank. The fuselage is constructed in a conventional half-shell construction. The structural parts are predominantly anodized . The construction was based on the fail-safe principle. The cell was designed for 18,000 flights (one flight corresponds to 1.8 flight hours). This has also been proven in fatigue tests. The permissible cabin differential pressure is 8.25 psi . The wing center box is designed and manufactured as an integral construction. The wings are attached to the two flange sides with high-strength expansion bolts. The main landing gear is connected to the lower side of the wing center box. The wing center box also serves as a center tank. The luggage compartment accessible from the inside is located above the wing center box. The equipment rooms (electrics, hydraulics, fuel, air conditioning and pressure supply) are located behind the wing center box. The equipment compartments are accessible from the outside through several maintenance hatches. The rear bulkheads are designed as connection points for the rudder unit and the two engines. The tail cone contains a braking parachute .
The windshields are spherical in shape and made of multiple layers of stretch acrylic . They are also electrically heatable and provided with an electrically conductive layer to dissipate static electricity. The bird strike security has been proven with appropriate tests . The left side window can be opened and also served as an emergency exit.
The mechanical flight control consists of rotating shafts with gears and bumpers without hydraulic power assistance. The control surfaces have a mass balance. Aileron and rudder are trimmed electrically, while the horizontal stabilizer is trimmed hydraulically. The landing flaps, slats and air brakes are operated hydraulically. As a result of the flight test accident with the HFB 320 V1, the HFB 320 was equipped with a stick-shaker and stick-pusher system that was controlled by an analog / digital computer. The system was used to warn the pilot in good time before the stall speed was reached (by shaking the control column / stick shaker); if the pilot did not react, the control column was pushed forward (stick pusher). The necessary control information was determined by the computer from speed, angle of attack, rate of change in angle of attack, air temperature and density as well as the position of the landing flaps. The HFB 320 was probably the first civil aircraft in the world to have such a system as standard.
The hydraulic system consists of two independent circuits with a pressure of 3000 psi. A hand pump in the cockpit can be used to operate an emergency circuit for important hydraulic functions (e.g. landing gear).
Electricity was generated using two 28 V direct current generators (one generator per engine). The generators also serve as starter generators for the engines. An external power supply is required for this. If an APU with a DC generator was installed, the engines could also be started with this (due to high maintenance costs, however, all APUs were gradually removed). Two rotating and one static converters convert the 28 volt DC voltage into 115 V 400 Hz AC voltage to supply the built-in avionics and other electrical devices. One or two NiCd batteries were available for the emergency power supply. In addition, two 115/200 V alternating current generators of unregulated frequency provided electrical de-icing.
The avionics are installed in a front radio rack behind the cockpit wall and another radio rack in one of the rear equipment compartments. The two radio racks offer enough space to install an avionics package according to customer requirements. The customer could choose between avionics packages from the manufacturers Sperry (Autopilot SP40) or Collins (Autopilot AP103). Equipment for approaches to CAT II ( instrument landing system ) is possible.
The aircraft has a three-legged landing gear. The main landing gear is attached to the fuselage and retracts forward into the fuselage. The nose landing gear is also retracted forwards. The chassis can be operated with all three hydraulic circuits. The nose landing gear can be controlled using a hand wheel in the cockpit. The brakes are equipped with an anti-skid system (similar to an anti-lock braking system in a car).
Pressure and air conditioning
Bleed air from the engines was used for air conditioning and pressurization of the cockpit and cabin. Parts of the bleed air were passed through a heat exchanger. The cooled air was then mixed again with the remaining bleed air via a mixing valve at which the desired cabin temperature was set. The cabin pressure was set via two pneumatically controlled outlet valves. It was controlled by a height regulator installed in the cockpit. Up to an altitude of 38,000 ft, a maximum internal cabin pressure of 7,250 ft (differential pressure = 8.25 psi) could be maintained. The ECM version had a second air conditioning system that was used exclusively to cool the jammers. In the event of failure of the cabin air-conditioning system, emergency operation to maintain pressure in the cabin could also take place.
The standard design of the cabin was the seven-seater version. However, an eleven or twelve-seater version would also have been possible. There is a toilet on the left in the passage between the cockpit and cabin. A cloakroom and pantry are installed opposite. The luggage compartment is accessible from the inside and is located behind the rear row of seats.
Two General Electric CJ610 engines were installed. The versions -1, -5 and -9 were used, which differ from each other in their increased thrust. The engine is a single-circle engine of the first generation of jet engines and was the only engine in this thrust class that was available as standard. The disadvantage of this engine was the high fuel consumption ( specific fuel consumption , sfc) of 0.97 lb / lbf × hr and the high noise emission (−9 version 103 dbA at 103% take-off thrust).
Auxiliary Power Unit
An auxiliary power unit of the type Saurer APU GT 15 with 15 bhp performance was installed in the rear fuselage. It was used to generate electricity for starting the engines without an external power supply and for air conditioning on the ground. The Saurer APU was the smallest auxiliary power unit in the world at the time. Because of the high maintenance and repair costs, the auxiliary power unit was gradually removed again.
The fuel was housed in the fuselage tank, the wing tanks and the wing tip tanks ("tip tanks"). The inside of the tanks was provided with a polyurethane paint and an anti-microbe coating. The first series aircraft had downdraft refueling. Later series aircraft were equipped with a central pressure refueling system. The fuel transfer from the fuselage tank and the tip tanks to the wing tanks was regulated automatically. This regulation also served to maintain the permissible center of gravity. The fuel in the tip tanks protruding far to the front should also reduce the aeroelastic bending of the wings at high flying weights. Each wing and tip tank had two fuel pumps. The fuselage tank had a single pump.
The leading edges of the engine air inlets were de-iced with hot bleed air from the respective engine compressor (extraction in stages 3 to 5) . The wing noses, the noses of the horizontal and vertical stabilizers, the slats and air conditioning intakes were electrically defrosted. For this purpose, the parts were provided with electrically heated rubber mats. The individual sections were controlled cyclically, as insufficient electrical energy was available to heat all areas at the same time. It was controlled by an electromechanical box containing a stepper motor with a contact roller. The electrical energy was generated by two 115/200 volts generators with an unregulated frequency. Electric de-icing was also used on the windshields.
HFB 320 ECM
1973 ordered the Federal Office of Defense Technology and Procurement eight aircraft HFB 320 ECM at MBB -Unternehmensbereich Hamburger aircraft in Hamburg-Finkenwerder (now Airbus site). With these aircraft the operators of air defense systems of the air force, army and navy, as well as during NATO exercises of other NATO countries, were trained in the detection of electronic faults and the application of countermeasures. In addition, tests were carried out to technically improve the interference immunity of air defense systems. The aircraft were partly (re) built from series overhangs. For the integration of the ECM system ( Electronic Counter Measures ; dt. " Electronic countermeasures ") extensive changes to the airframe and the systems had to be made. The devices of the ECM system were developed and built by the Italian company Elettronica SpA in Rome. The system consisted of a receiving and transmitting system operated by a coordinator and two interferers . A navigation system from Marconi and a UHF system were available to the coordinator.
The RMB6 receiver can be tuned at a defined speed over the frequency range 1 to 18 GHz. The input signals came from an antenna installed on the underside of the fuselage under a radome . The antenna could either be aligned at a certain angle to the longitudinal axis of the aircraft or operated in a rotating manner. The UYD2 video analyzer evaluated the signals with regard to frequency, modulation form and modulation sequence (pulse repetition frequency).
A multifunctional modulator was used to control the six ULQ jammers . With the multifunction modulator, the interference frequency, the modulation form and frequency as well as the pulse repetition sequence could be set. The jammers were housed in the luggage compartment of the HFB 320. A second air conditioning system was installed for cooling. The jammers covered a frequency range from 1–18 GHz and were equipped with a traveling wave tube of variable frequency. The transmission power was conducted via aluminum waveguides to the antennas (horn radiators) in the nose and tail of the fuselage. The antennas were attached to an antenna mast and could be aimed at the target by the radio operator. The antennas were covered with a specially shaped radome.
On the basis of the operational experience, the ECM system of the HFB 320 was modified from 1984 to 1989 in order to further increase the performance (HFB 320 ECM adaptation measures). For this purpose, modified and additional devices have been built into the HFB 320ECM at the DASA plant in Lemwerder .
With the HFB 320 ECM, the Air Force and NATO partners had a high-performance ECM training system at their disposal, which was based at the Fighter Bomber Wing 32 in Lechfeld until it was gradually phased out from 1994 onwards due to the changed security situation.
From the first flight in 1964 to the end of operations in 2004, a total of nine HFB 320s were destroyed or irreparably damaged. A total of 21 people were killed in six of the accidents.
The fatal accidents of 1965 and 2004 are described in the history section above . Other examples:
- On December 18, 1970, General Air's HFB 320 with the aircraft registration D-CIRO failed on a transfer flight from Hamburg to Cologne / Bonn . In order to get into visual flight weather conditions , the pilots flew towards the North Sea. In the absence of an airport visible between the clouds, an emergency landing with retracted landing gear was carried out on the beach on the Dutch island of Texel . Both pilots survived. The already damaged machine was finally demolished during the rescue.
- On June 29, 1972, an Inter City Flight ( D-CASY ) HFB 320 crashed while attempting to take off from Blackpool Airport (England). The elevator lock had not been released before take-off, which prevented the machine from taking off. The start was aborted at very high speed. The plane rolled over the end of the runway and a railway line and came to a standstill at a holiday camp. Seven of the eight inmates were killed.
- On November 22, 1976, the HFB 320 ECM with the German military registration number 16 + 22 had an accident near Ziemetshausen after it collided in the air with a Fiat G.91 of the Luftwaffe 50 (registration number 34 + 49 ) from Fürstenfeldbruck . The five crew members of the Hansa jet were killed, the two pilots of the fighter jet were able to save themselves with the ejection seat. This only fatal accident with an HFB 320 in the operation of the Bundeswehr - at that time part of the Telecommunications Training and Experimental Regiment 61 - was due to the fact that the crew of the Fiat G.91 left an allocated air space for aerial combat maneuvers (so-called temporary reserved airspace ), without switching back to instrument flight rules (IFR) as intended, and collided with the stern of the HFB 320 flying according to IFR at an altitude of almost 3,000 meters. The pilot of the G.91 had to answer for the accident in court.
|crew||2 (ECM: 5)|
|Passengers||12 (ECM: 0)|
|Wing profile||NACA 65A (1.5) 13 inside, NACA 63A (1.8) 11 outside|
|Cabin length||4.58 m|
|Max. Cabin width||1.90 m|
|Max. Cabin height||1.74 m|
|Operating empty mass||5000 kg|
|Takeoff mass||(depending on the version) 8500 kg / 9200 kg / 9600 kg|
|Cruising speed||819 km / h|
|Top speed||Mach 0.83|
|Service ceiling||11,600 m|
|Range||Max. 2370 km (1455 km with 12 passengers, 2320 km with 4 passengers)|
|Engines||two General Electric CJ 610-1 / 5/9 with 12–13 kN thrust each|
Remain in Germany
Since the end of 2004 the association “A Hansa Jet for Hamburg” has been trying to buy a machine of this type and get it ready to fly. In May 2007 a well-preserved Hansa Jet was bought by the German Armed Forces for this purpose. In August it was brought from Manching to its current location in Hamburg, where in a few years' time, restored and equipped with engines, it could fly again as a historic airplane or flying memorial. On January 17, 2010, the Hansa Jet was transported with road scooters from Lufthansa Technik in Fuhlsbüttel to Airbus in Finkenwerder. The association wants to make the aircraft airworthy again on the factory site on which this jet was originally built.
- The HFB 320 (Ex FlgBschft BMvg) tactical license plate 16 + 06 (S28) and HFB 320 ECM (formerly JaboG 32 3rd Stff) tactical license plate 16 + 26 (S43) are exhibits of the Air Force Museum on the former airfield Berlin-Gatow .
- The HFB 320 V2 is in the Deutsches Museum in Munich.
- The HFB 320 S1 is on the Airbus site in Hamburg-Finkenwerder.
- An HFB 320 (civil) is in the Aviation Museum Laatzen-Hannover .
- An HFB 320 (D-COSA) is in the Gerhard Neumann Museum in Niederalteich.
In 1969 project plans were published with the aim of a further development aimed at the US market with the designation HFB 330 Hansa Fan Jet . Thereafter, the new aircraft should go into flight testing in 1971 and receive FAA approval in 1972. Series production was then to start in full in 1973 with three units per month. The unit price was 6.5 million DM. It was planned to sell around 200 machines on the American market by 1980. The HFB 330 was to be powered by two Garrett ATF-3 turbofan engines, each with 18.0 kN (4040 lbs) of thrust. It should be able to carry 10, 14 or 16 passengers in different versions. The range was given as around 4,500 km and the maximum take-off weight with 10,200 kg.
In 1977 it was investigated to retrofit the already delivered HFB 320 with the Garrett TFE 731 engine (HFB 320 Fan Jet) in order to reduce fuel consumption and reduce noise emissions. Due to the high development costs and the small number of units, the project was not pursued any further.
- HW Laumanns: Type compass German commercial aircraft since 1919 , Motorbuch, Stuttgart 2008, ISBN 978-3-613-02975-0 , pp. 110–111
- hansajet.de ( Memento from February 28, 2005 in the Internet Archive ).
- Accident report HFB 320 D-CHFB , Aviation Safety Network (English), accessed on October 6, 2019.
- Provisions of the CAR 4b approval. (PDF; 631 kB).
- Accident report HFB 320 N604GA , Aviation Safety Network (English), accessed on January 12, 2018.
- FlugRevue. 2/2008, pp. 92-95, comeback attempt (HFB 320).
- Saurer GT15 Gas Turbine Engine on gasturbineworld.co.uk, English, accessed January 12, 2018
- HFB 320 Hansa Jet Technical Description. August 1968.
- HFB 320 Hansa Jet Civil and Military Program. October 1968.
- HFB-320 accident statistics , Aviation Safety Network (English), accessed on January 12, 2018.
- Accident report HFB 320 D-CIRO , Aviation Safety Network (English), accessed on June 16, 2016.
- Accident report HFB 320 D-CASY , Aviation Safety Network (English), accessed on June 16, 2016.
- augsburger-allgemeine.de .
- Accident report HFB-320 16 + 22 , Aviation Safety Network (English), accessed on December 18, 2017.
- Accident report Fiat G.91 34 + 49 , Aviation Safety Network WikiBase , accessed on December 18, 2017.
- Dangerous mixture . In: Der Spiegel . No. 21 . Hamburg July 3, 1978 (  [accessed on September 6, 2016]).
- The Incomplete Guide to Airfoil Usage , page of the Applied Aerodynamics Group at the UIUC ( memento of April 20, 2010 in the Internet Archive ), accessed on October 6, 2019
- An oldie flying low through the Hanseatic city. Abendblatt.de.
- f-104.de .
- Flight Revue. 11/69, p. 22.