An aerobatic trainer / tourer, the prototype first flying in 1983.
MDB Flugtechnik AG was founded 1991 to continue development of the MD3-160, as begun by MDC Max Datwyler AG, which was being manufactured in Malaysia by SME Aviation as the MD3-160 AeroTiga. The first Malaysian-built example in flew 1995.
MD-3-160
Engine: Lycoming O-320-D2A
Seats: 2
Switzerland.
Max Dätwyler & Co, based at Bleinbach-Leupenthal, produced in 1960 a glider-tug based on the Piper Super Cub, designated MDC-Trailer. Produced subsequently a modernised version of the Bucher Bu 131 Jungmann, known as the Lerche. First flew in 1983 the prototype MD-3 Swiss Trainer.
Switzerland
Founded 1991 to continue development of the MD3-160, as begun by MDC Max Datwyler AG, which was being manufactured in Malaysia by SME Aviation as the AeroTiga.
Wallace and Robert McNair started the Mynah II design in Septem¬ber 1988, intended right from the start for series production, a two seater at the top end of the microlight performance range. This aircraft had no commonality with the earlier single seat Mynah aircraft, although both were designed by Wallace and Robert McNair of Auckland, New Zealand.
The fuselage is a one piece moulded fibreglass unit, with integral verti¬cal fin and bottom wing fairings. Moulded in at construction time are wooden longerons, to which the engine mount is bolted at the firewall, and strength is added by the compound curves everywhere, the only straight surface being on the bottom be¬tween the wings. Bulkheads are located around the cockpits and form the structural unit on which the wings, struts, wires and fibreglass landing gear legs are mounted.
The wings, of Clark Y aerofoil, have folded aluminium channel extrusions for the spars, pressed aluminium ribs and Mylar covering, an aluminium leading edge, laced along the lead¬ing edge and each end, with the lacing covered by tips and leading edges, applied after covering. They have marked forward stagger, the bottom wing rear spar passing behind the rear seat and the top wings with a large amount of sweepback to keep the centre section well forward, clear of the front cockpit. Fuel tanks with a total capac¬ity of 50 litres are incorporated in the in¬board ends of the bottom wing leading edges.
Everything is designed around the 390 kg microlight category and standard 4G loading. Empty weight is 170 kg, allowing a pay¬load total of 220 kg, plenty for two occu¬pants, full fuel and a bit more. The Mynah II has a safe endurance of two and a half hours. Motive power is a two cylinder horizon¬tally opposed two stroke Arrow engine from Italy, pulling 65 hp at 6800 rpm, with the three blade carbon fibre propeller of 66 in diameter geared down at 2.77/1.
It was designed with an eye to production but this never eventuated.
ZK-FWT (c/n 001/MAANZ/450) was built by the McNairs and also by Alan Stewart of Tuatapere, to whom the aircraft was first registered on 25/10/90. It flew well with a cruise of around 70 mph. Empty weight was around 220 Kg and MAUW was 449 Kg.
It was sold to RA Hansen of Huntly on 30/8/93. It is still registered and it is kept in a hangar at Glen Murray, although I believe it hasn’t flown for several years.
Designed and built by Wallace McNair, Auckland, NZ, and owing much to the Lincoln Sports design, the Mynah has a unique folding fuselage for transportation by trailer. The wings are therefore able to be permanently rigged while the wire bracing from the wing struts to the rear fuselage takes only a matter of minutes to rig. The engine is a two-cylinder “half-a-VW”.
Hi I currently own the mcnair mynah pictured and one partialy built, mine has a rotax 447 engine although i have seen one with a 503 rotax. There were about 6 built and 3 in flying condition that i know of.
Michael Jones 13 December 1013
Engine: Kornatsu Zenoah, 40hp
Cruise: 50 mph
Stall: 20 mph
Engine: ½ VW
Derived from the British Aerospace Hawk advanced trainer, the US Navy’s carrier-capable T-45A Goshawk prototype was scheduled to fly before the end of 1987, with service entry due in 1990. The Hawk was selected in 1981 as the aircraft element of the new VTX-TS training system, and a fixed-price contract covering the first three production lots and 15 simulators was signed in May 1986. Total cost of the T-45TS package, including 300 production aircraft, two prototypes, simulators, computerised instruction and integration system, and logistics support is estimated at $4,500 million. British Aerospace is the principal airframe subcontractor, building the wings, rear fuselage, canopy, and flight controls, although final assembly and some component manufacture will be undertaken by McDonnell Douglas in the USA.
McDonnell-Douglas / BAe T-45 Goshawk Article
Changes from the basic Hawk design include a twin-wheel nose gear for catapult launching, a strengthened maingear to allow high-sink-rate landings, an arrester hook, rear side-fuselage airbrakes, and a cockpit modified to USN requirements. The empty weight of the T-45A will be 4,261kg, and maximum take-off weight 5,787kg, with an internal fuel load of 1,363kg. Approach speed will be 222km/hr (121 kt), maximum level speed Mach 0.85, and average fuel consumption 620kg/hr on a typical training sortie. Weapons delivery capability for armament training were be incorporated.
The T-45 Goshawk, of which the Navy owns 193 aircraft, is a jet trainer fleet used by the Navy and Marine Corps to qualify new pilots. Originally produced by what is now Boeing and derived from an earlier British aircraft made by BAE Systems, its first iterations joined the US Navy’s fleet in the 1990s.
BAe / Boeing T 45 C Goshawk
Engine: Rolls Royce/Turboméca F 405-RR401 (Adour Mk. 871), 25977 N / 2648 kp
Length: 39.272 ft / 11.97 m
Height: 13.419 ft / 4.09 m
Wingspan: 30.807 ft / 9.39 m
Wing area: 179.651 sq.ft / 16.69 sq.m
Max take off weight: 14083.3 lb / 6387.0 kg
Weight empty: 9399.9 lb / 4263.0 kg
Max. speed: 543 kts / 1006 km/h
Initial climb rate: 6982.28 ft/min / 35.47 m/s
Service ceiling: 42503 ft / 12955 m
Wing load: 78.52 lb/sq.ft / 383.0 kg/sq.m
Range: 999 nm / 1850 km
Crew: 2
Hardpoints: 3
The genesis of the Explorer dates to 1986, when company engineers hit upon the idea of using the latest technology, such as an all-composite main rotor and MDHS’ own no-tail-rotor (NOTAR) anti-torque system, as a basis for a new eight-seater design which would give excellent performance at affordable cost. The MD Explorer is the first commercial helicopter totally designed using computer-aided design techniques and only after a detailed market survey of over 177 operators asking them what they wanted from a new utility helicopter in terms of flight performance and general layout in a 1800 to 3600kg helicopter.
McDonnell-Douglas MD-900 / MD-902 Explorer Article
MDHS decided to go ahead with design work in January 1989 with a senior advisory council formed from risk-sharing partners in the $200 million programme. The Explorer is created using computer-aided design (CAD) techniques. The Explorer is the first helicopter to have a major portion of its primary structure constructed from composites. This is most evident in the fuselage, which is manufactured by Hawker de Havilland in Australia. Skins, floors, mb/keel beam and aft-fuselage assemblies are made from a pre-impregnated carbon-fibre composite with a toughened epoxy resin system produced by Hexel. Hawker de Havilland refined manufacturing techniques after the first three fuselage units and standardised on a final design which is around 10% lighter than the development fuselages, weighing in at just 260kg. Metallic parts consist of the titanium roof which provides protection from fire in the engine area, the main frames, fittings and forward-cockpit structure. Two aluminium plough beams form the primary structural support for the nose and provide enhanced crash-protection. In the event of a forward impact with the ground, the beams are designed to keep the nose of the helicopter from tipping down. In the passenger configuration, the Explorer’s 1.44m-wide cabin provides enough space for two rows of three 480mm seats , with a seventh passenger seated in the co-pilots position. Without seats, the helicopter has a completely flat floor which is accessible via a rear-access door and large sliding doors on either side of the cabin. The tailboom and empennage are all-composite primary structures made by MDHS using the same carbon composite and toughened resin as the fuselage. Like the fuselage, the early tailboom design was altered slightly for the final-production configuration to give a 25% weight saving. As the tailboom is hollow to accommodate the NOTAR system, it has aerodynamic surfaces on the inside, as well as the outside. Slots run the length of the right-hand side of the boom to allow air to escape and create the Coanda effect at the heart of the NOTAR principle.
Initially known as MDX, then MD 900 (proposed MD 901 with Turbomeca engines was not pursued. Hawker de Havilland of Australia designed and manufactures airframe; Canadian Marconi tested initial version of integrated instrumentation display system (IIDS) early 1992; Kawasaki completed 50 hour test of transmission early 1992. Other partners include Aim Aviation (interior), IAI (cowling and seats) and Lucas Aerospace (actuators).
Ten prototypes and trials aircraft, of which seven (Nos. 1, 3-7 and 9) for static tests, were built. The first flight (No.2/N900MD) was on 18 December 1992 at Mesa, Arizona, followed by No.8/N900MH 17 September 1993 and No.10/N9208V 16 December 1993; first production/demonstrator Explorer (No.11/N92011) flown 3 August 1994.
FAA certification 2 December 1994; first delivery 16 December 1994; JAA certification July 1996; FAA certification for single-pilot IFR operation achieved January 1997. Type certificate transferred to MDHI on 18 February 1999.
This new technology helicopter received type certification on 21 December 1994 from the FAA which was only 23 months after first flight. This was one of the shortest certification periods ever recorded for a new helicopter and was also the first new design passenger and utility rotorcraft certified by the FAA in more than ten years.
FAA certification of uprated PW207E engine achieved in July 2000, providing 11% more power for take-off and 610m increase in hovering capability OEI in hot-and-high conditions; first delivery of PW207E-engined Explorer to Police Aviation Services, UK, 27 September 2000. “100th production” Explorer (actually 89th overall, including prototypes) delivered 1 March 2002 to Tomen Aerospace Corporation of Japan for ENG operations by Aero Asahi of Hiroshima. Total fleet time stood at more than 120,000 hours by December 2002.
MDHS begun delivery of the Explorer with a target direct-operating cost of $389/h and a base price of $3.16 million at 1995 exchange rates.
The Explorer has been built largely from composite materials and is powered by twin Pratt & Whitney Canada PW 206A turboshafts and has a maximum gross weight of 2950kg. It can lift 1150kg internally, or 1350kg externally and weighs only 1350kg empty. The helicopter incorporates a range of new technologies to improve safety and performance and reduce operating costs. These include the NOTAR yaw control system, composite, bearingless main rotor with five blades. Digital avionics including FADEC, diagnostics and an Integrated Instrument Display System. The liquid crystal Integrated Instrument Display System (IIDS) replaces traditional cockpit instruments by presenting aircraft operating information in a digital format and icon symbology on two six-inch screens. The system also records operating data for on-board health and usage monitoring, providing technicians with accurate information for performing maintenance functions.
The NOTAR anti-torque system features all-composites five-blade rotor of tapered thickness with parabolic swept outer tip with bearingless flexbeam retention and pitch case; tuned fixed rotor mast and mounting truss for vibration reduction; replaceable rotor tips; maximum rotor speed 392 rpm; modified A-frame construction from rotor mounting to landing skids protects passenger cabin; energy-absorbing seats absorb 20 g vertically and 16 g fore and aft; onboard health monitoring, exceedance recording and blade track/balance.
Mechanical engine control from collective pitch lever is back-up for electronic FADEC. Automatic stabilisation and autopilot available for IFR operation. The transmission overhaul life 5,000 hours; glass fibre blades have titanium leading-edge abrasion strip and are attached to bearingless hub by carbon fibre encased glass fibre flexbeams; rotor blades and hub on condition.
The baseline MD 900 is powered by two Pratt & Whitney Canada PW206E turboshafts with FADEC, each rated at 463kW for 5 minutes for T-O, 489kW for 2.5 minutes OEI and 410kW maximum continuous. Transmission rating 820kW for T-O, 746kW maximum continuous, 507kW for 2.5 minutes OEI and 462kW maximum continuous OEI.
Fuel contained in single tank under passenger cabin, capacity 564 litres, of which 553 litres are usable. Single-point refuelling; self-sealing fuel lines.
Accomodation is for two pilots or pilot/passenger in front on energy-absorbing adjustable crew seats with five-point shoulder harnesses/seat belts; six passengers in club-type energy-absorbing seating with three-point restraints; rear baggage compartment accessible through rear door; cabin can accept long loads reaching from flight deck to rear door; hinged, jettisonable door to cockpit on each side; sliding door to cabin on each side.
Hydraulic system, operating pressure 34.475 bar.
With 14 feet of flat floor space in the rear cabin, the Explorer is expected to undertake a multitude of civil missions from general utility to offshore transportation, corporate flight, tourist flights and air medical services. In the EMS configuration the Explorer can accommodate two patients, two attendants and life support equipment in addition to the flight crew.
The 100th Explorer registered in 2002 (to become seventh for Netherlands police); total of 108 manufactured by December 2002; first delivery 16 December 1994 to Petroleum Helicopters Inc (PHI) which ordered five; second delivery (N901CF) December 1994 to Rocky Mountain Helicopters for EMS duties with affiliate Care Flight unit of Regional Emergency Medical Services Authority (REMSA) in Reno, Nevada. Total of two delivered in 1994, 12 in 1995, 15 in 1996, one in 1997, four in 1998, 11 in 1999, 16 in 2000, 20 in 2001 and four in 2002; initial (MD 900) series comprised 40 aircraft including three flying prototypes; FW207E engine from 64th production (67th overall) aircraft.
MD Enhanced Explorer: Improved version, announced September 1996; originally MD 902, but now known as “902 Configuration”. Main features include Pratt & Whitney Canada PW206E engines with increased OEI ratings; transmission approved for dry running for 30 minutes at 50% power; improved engine air inlets, NOTAR inlet design and engine fire suppression system, and more powerful stabiliser control system, resulting in 7% increase in range. 4% increase in endurance and 113kg increase in payload over Explorer. First flight (N9224U; c/n 900-0051, 41st Explorer) 5 September 1997, FAA certification to Category A performance standards (including continued take-off with one failed engine) and single-pilot IFR operation achieved 11 February 1998; JAA certification for Category A performance achieved July 1998. Retrofit kits to convert Explorers to Category A standard. First Enhanced Explorer delivery in May 1998 to Tomen Aerospace of Japan. PW206E replaced by PW207E from late 2000, beginning at c/n 900-0077, allowing further MTOW increase to 2,948kg.
MH-90 Enforcer: Beginning March 1999, under a programme code-named Operation New Frontier, the US Coast Guard used two leased MD 900 Explorers for shipboard anti-drug smuggling operations. Armed with a pintle-mounted M240 7.62mm minigun at the door station. In September 1999 the MD900s were exchanged for two leased MD 902 Enhanced Explorers. These subsequently replaced by Agusta A 109s. Six delivered to Mexican Navy at Acapulco (two each respectively in May and December 1999 and April 2000) for anti-drug operations, equipped with 12.7mm General Dynamics GAU-19/A Gatling guns, and 70mm rocket pods; further four in process of delivery. Weapons qualification trials were completed at Fort Bliss, Texas in November 2000.
Combat Explorer: Displayed at Paris Air Show, June 1995; demonstrator N9015P (No.15), an MD 900 variant. Can be configured for utility, medevac or combat missions; armament and mission equipment may include seven- or 19-tube 70mm rocket pods, 12.7mm machine gun pods, chin-mounted FLIR night pilotage system and roof-mounted NightHawk surveillance and targeting systems. Combat weight 3,130kg; two P&WC PW206A engines. No customers announced by January 2000, but N9015P became one of initial two MH-90s (with third prototype, N9208V).
February 19, 1999: Boeing sold MD commercial line to RDM The dutch company bought the ex Mc Donnell Douglas models MD 500E and MD 530F single-engine helicopters with conventional tail rotors, the MD 520N and MD 600N single-engine NOTAR helicopters and the MD Explorer series of twin-engine, eight-place helicopters.
Costs: US$2.285 million (2002); direct operating cost US$408.11 (2002) per hour.
McDonnell Douglas MD 902 Explorer
Engine: 2 x Pratt & Whitney Canada PW206E, 630 shp
Length: 32.316 ft / 9.85 m
Height: 12.008 ft / 3.66 m
Rotor diameter: 33.825 ft / 10.31 m
Wing area: 3939.624 sqft / 366.0 sq.m
Max take off weight: 6504.8 lb / 2950.0 kg
Weight empty: 3214.9 lb / 1458.0 kg
Max. speed: 160 kts / 296 km/h
Cruising speed: 140 kts / 259 km/h
Initial climb rate: 2795.28 ft/min / 14.2 m/s
Service ceiling: 18497 ft / / 5638 m
Wing load: 1.64 lb/sq.ft / 8.0 kg/sq.m
Range: 313 nm / 580 km
Crew: 2
Payload: 8pax
MD Explorer
Engine: 2 x Turbomeca Arrius 2C
Instant pwr (Turbomeca engine): 480 kW.
Rotor dia: 10.3 m
MTOW: 2700 kg
Useful load: 1165 kg
Max cruise: 150 kts
Max range: 600 km
Seats: 8
MD Explorer
Engine: 2 x P&WC PW206A
Gross wt: 2,722kg
Empty operating wt: 1,481kg
Useful load: 1,163kg
Fuel capacity wt (600litres): 438/472kg
Main rotor dia: 10.34m
Length: 9.86m
Height: 3.66m
Skid width: 2.23m
Passengers: 7.
Crew: 1
Max cruise speed @ ISA 38oC: 135kt (@sea level ISA: 139kt)
Max range: 530km
Max endurance: 3.5hr
Hover Out of ground effect @ ISA: 3,353m (@lSA+20o: 2,073m)
Hover in ground effect @ ISA 3901m (@lSA+20o: 2,621m)
Climb rate: 14.2m/s
Ceiling: 20,000ft
MD 900 Explorer
Engines: 2 x Pratt & Whitney PW 206B turboshaft, 469kW
Rotor diameter: 10.31m
Length with rotors turning: 11.83m
Fuselage length: 9.85m
Height: 3.66m
Fuselage width: 1.63m
Max take-off weight: 3057kg
Empty weight: 1481kg
Max speed: 278km/h
Cruising speed: 250km/h
Rate of climb: 14.2m/s
Hovering ceiling: 3840m
Service ceiling: 6100m
Range: 530-600km
Payload: 1360kg
Crew: 1-2
Passengers: 6
On 8 November 1994, McDonnell Douglas announced their plans to develop an eight-place version of their popular MD520N helicopter. They surprised the world’s press in January 1995 when they flew their new helicopter to Heli-Expo 95 in Las Vegas, Nevada. The prototype, then known as MD 630N (N630N, converted from MD 530F demonstrator), first flew 22 November 1994, 138 days after project approval. After their public debut at Heli-Expo the first year’s production was sold out on the first day.
McDonnell-Douglas MD-600 Article
Production go-head was given on 28 March 1995, at which time designation changed to MD 600N; and a prototype was first flown with production standard engine and rotor system on 6 November 1995.
The 600N has a 33in lengthened fuselage centre section with double, centre opening doors, which gives access to a six-foot long flat floor with seating for five passengers in this rear cabin and three across the front seats. The complete fuselage of these helicopters are built under contract by helicopter manufacturer Kaman Aerospace. The six bladed fully articulated main rotor system shares many components with the MD500 series machines, and power comes from an 800-shp Rolls-Royce Allison 250-C47M turboshaft engine, which is derated to 600 shp for take-off and 530 shp for maximum continuous. The engine is equipped with FADEC as well as a manual backup hydro-pneumatic fuel system.
Production prototype (N600RN) first flown 15 December 1995, and became certification test vehicle leading to FAR Pt 27 certification, but was destroyed in ground fire 28 May 1996, following emergency landing after rotor/tailboom strike during abrupt control reversal tests. This resulted in changes to tailboom/rotor clearance; third prototype (N605AS) flown 9 August 1996; further accidents to N630N on 4 and 21 November 1996 and on 18 January 1997, all during autorotational descents, culminated in total loss and delayed certification and first delivery, originally scheduled for 18 December 1996, to 15 May and 6 June 1997, respectively. MD 600N certified on MD500 certificate.
The FAA Certification was received on 15 May 1997. The first delivery was on 6 June 1997, N605AS, to AirStar Helicopters.
The 630N features a stretched MD 520N airframe (less than 1% new parts) by means of 0.76m plug aft of cockpit/cabin bulkhead and 0.71m plug in tailboom, combined with more powerful engine, uprated transmission and six-blade main rotor. Cabin has flat floor to assist cargo handling, and will feature quick-change interior configurations to suit multiple-use operators. Intended for civil, utility, offshore, executive transport, medevac, aerial news gathering, touring, law enforcement and other noise-sensitive operations; also adaptable for armed scout, utility and other military missions.
Powered by one 603kW Rolls-Royce 250-C47M turboshaft, derated to 447kW for T-O (5 minutes) and 395kW maximum continuous, with FADEC. Transmission manufactured from WE43A magnesium alloy for lower weight, greater strength and enhanced corrosion resistance, rating 447kW. Fuel contained in two crashworthy bladder tanks in lower fuselage, total capacity 440 litres, of which 434 litres are usable.
The electrical system comprises 28V 200Ah starter-generator and 28V 17Ah Ni/Cd battery. 24V auxiliary power receptacle inside starboard cockpit door standard.
In July 1998, Boeing completed a year-long envelope expansion programme for the MD 600N leading to FAA approval for operation at a density altitude of 2,135m at a T-O weight of 1,746kg and at a density altitude of 1,220m at a T-O weight of 1,860kg. Other performance enhancements approved by the FAA included provision for doors-off operation at speeds up to 213km/h, operation at temperatures -40°C/52°C, lifting up to 968kg on the external cargo hook, making slope landings up to 10° in any direction, operation with emergency floats and for installation of a movable landing light and additional wire strike protection on the fuselage. The MD 600N also completed HIRF trials at NAS Patuxent River, Maryland. Yaw-stability augmentation system (Y-SAS) was under development during 2000, aimed at reducing pilot workload during extended flights and in turbulent conditions.
Total of 68 registered by May 2003. Launch customer AirStar Helicopter of Arizona (two, of which first delivered 6 June 1997); Saab Helikopter AB of Sweden and Rotair Limited of Hong Kong ordered one each in June 1995; other customers include Guangdong General Aviation Company (GGAC) of the People’s Republic of China, which took delivery of one MD 600N in November 2000, during Airshow China 2000 in Zhuhai, Los Angeles County Sheriff’s Department Aero Bureau (three), Orange County, California, Sheriff’s Department, Indianapolis, Indiana. Police Department (one), Presta Services of France (one), Turkish National Police, which ordered 10 in December 2000 for delivery during 2002 (subsequently postponed to 2003), UND (University of North Dakota) Aerospace (one), West Virginia State Police (one) and the US Border Patrol (45, of which 11 delivered by end of 1998. when procurement halted pending evaluation of UAVs for border patrol role). Deliveries totalled 15 in 1997, 21 in 1998, six in 1999, seven in 2000, two in 2001 and two in 2002.
Costs: US$1.315 million (2002).
February 19, 1999 : Boeing sold MD commercial line to RDM The dutch company bought the ex Mc Donnell Douglas models MD 500E and MD 530F single-engine helicopters with conventional tail rotors, the MD 520N and MD 600N single-engine NOTAR helicopters and the MD Explorer series of twin-engine, eight-place helicopters.
MD600N
Engine: Allison 250-C47, 600 shp / 589kW
Main rotor diameter: 8.4m
Length with rotor turning: 11.2m
Height: 2.9m
Max take-off weight: 1860-2123kg
Empty weight: 875kg
Max internal payload: 984kg
Max external payload: 1247kg
Max speed: 282km/h
Cruising speed: 248km/h
Service ceiling: 6100m
Hovering ceiling, IGE: 3200m
Hovering ceiling, OGE: 2875m
Range: 335km
Endurance: 3.7hr
Seats: 8
MD-630N
Engine: Allison 250-C30, 600 shp
Seats: 7/8
MTOW: 4100 lbs
Max cruise: 134 kts
Range: 335nm
ROC: 1700 fpm
Max op alt: 20,000 ft
Max external load: 2750 lb
Max internal load: 2170 lb
Military variants known as Defenders (AH-6E, MH-6F) carry TOW missiles, FLIR, mast-mounted sight, etc.
The Model 530 Defender (has refined aerody¬namics and more power the OH-6), and AH-6 (Model 530 version for US Special Forces).
February 19, 1999: Boeing sold MD commercial line to RDM The dutch company bought the ex Mc Donnell Douglas models MD 500E and MD 530F single-engine helicopters with conventional tail rotors, the MD 520N and MD 600N single-engine NOTAR helicopters and the MD Explorer series of twin-engine, eight-place helicopters.
Commercial MD 520N and uprated (485 kW Rolls Royce 250-C30) MD 530N NOTAR helicopters announced February 1988 and officially launched January 1989. The first production prototype MD 530N (N530NT) flew on 29 December 1989, but this variant not pursued.
Flight testing of the MD 530N indicated capabilities greater than expected. With only 25.2 hours logged, a series of aerobatic manoeuvres were performed during June 1990, including loops, rolls, hammerheads and Split ‘S’ manoeuvres. In other tests the envelope was expanded to a maximum internal gross weight of 33500 lb / 1520 kg.
MD530
Engine: 1 x Allison 250- C20B turboshaft, 420 shp (313 kW)
MD530F
Engine: 1 x Allison 250-C30, 650 shp
Instant pwr: 313 kW
Rotor dia: 8.35 m
MTOW: 1405 kg
Useful load: 685 kg
Max cruise: 135 kts
Max range: 381 km
HIGE: 14,300 ft
HOGE: 12,000 ft
Crew: 1
Pax: 3
Seats: 5
530MG Defender
Engine: 1 x Allison 250-C30
Installed pwr: 317 kW
Rotor dia: 8.4 m
Fuselage length: 9.8 m
No. Blades: 5
Empty wt: 664 kg
MTOW: 1610 kg
Payload: 901 kg
Max speed: 240 kph
ROC: 505 m/min
Ceiling: 4200 m
HIGE: 2315 m
HOGE: 1770 m
Fuel cap (+aux): 240 lt ( 80 lt )
Range: 443 km
Crew: 1
Pax: 5
In 1976 engineers at McDonnell Douglas Helicopter Company (then Hughes) decided to explore the theories of Henri Marie Coanda (1885-1972), a Romanian-born aeronautical engineer and inventor, who put forward the concept that air flowing over a curved surface tends to follow the curve of that surface. The “Coanda Effect” is seen working when air flows over the surface of an airfoil. Under this effect, the aerody¬namics of the tailboom itself could be tapped to provide the bulk of the anti-torque force required. It is this principle which is at the heart of the NOTAR system embodied in the MD520N. The front half of the helicop¬ter is virtually identical to the MD 500E, but in place of a conventional tailboom and tail rotor mechanism, the MD 520N has a variable pitch fan totally enclosed within the tailboom, circulation control slots on the side of the boom, and vertical stabilizers and direct jet thruster. The variable pitch fan is driven off the back of the Allison 250-C20R turboshaft engine and, with help from the main rotor system down-wash, draws air via a grill into the enclosed tailboom, and provides low-pressure, high-mass airflow. Air is forced out through the circulation slots on the right side of the boom. Air exits the slots at about four times the velocity of the rotor downwash, which keeps the downwash attached to the curvature of the boom, resulting in the horizontal equivalent of lift, just like a vertical wing, and the Coanda Effect generates anti-torque force.
The direct jet thruster is located at the end of tailboom on the left side, and provides directional control plus assists with anti-torque. Even the engine exhaust stack helps out here, as it is canted to the left. However the bulk of the anti-torque required (eg 60-70 percent in hover) is provided by the Coanda Effect. Directional control above in forward flight above about 20 knots comes largely from the left vertical stabilizer, which is linked to pilot’s pedals. The effectiveness of this system is such that the MD 520N is approved for hovering in 30 knot crosswinds, and has been flown sideways at speeds signifi-cantly higher.
The first flight of an OH-6A NOTAR concept-demonstrator was made on 17 December 1981. The commitment to full-scale development and production was made in 1987. An extensive modifications during 1985 with second blowing slot, new fan, 250-C20B engine and MD 500E nose, led to flight testing resuming on 12 March 1986 and completed in June. The demonstrator was retired to US Army Aviation Museum, Fort Rucker, Alabama, October 1990.
Commercial MD 520N and uprated (485 kW Rolls Royce 250-C30) MD 530N NOTAR helicopters announced February 1988 and officially launched January 1989. The first production prototype MD 530N (N530NT) flew on 29 December 1989, but this variant not pursued.
First flight 520N (N520NT) on 1 May 1990 and first production 520N 28 June 1991. The 520N was certified on 12 September 1991 on the MD500 type certificate and the first production aircraft 520N (N521FB) delivered to Phoenix Police Department 31 October 1991. MD 520N set new Paris to London speed record in September 1992, at 1 hour 22 minutes 29 seconds.
The structure is the same as the MD 500E/530F, except graphite composites tailboom; metal tailplane and fins; new high-efficiency fan with composites blades fitted in production aircraft. NOTAR system components now have twice the lifespan of conventional tail rotor system assemblies. During 1993, NOTAR system components’ warranty increased from two to three years. Thicker fuselage skins, to reduce surface rippling, was to be introduced during 2001.
The single Rolls-Royce 250-C20R turboshaft, derated to 317kW for T-O (5 minutes) and 280kW maximum continuous. Improved, heavy-duty transmission, rating 447kW, derated to 317kW for T-O, 280kW maximum continuous, on production aircraft from June 1995. Fuel capacity 235 litres.
Believed to be the quietest turbine helicopter, based on FAA certification test noise figures, the main rotor rpm 477; main rotor tip speed 208m/s; NOTAR system fan rpm 5,388. A redesigned diffuser in NOTAR tailboom and revised fan rigging was introduced from early 2000 and available for retrofit; combined with uprated Rolls-Royce 250-C20R+ engine; these improvements increase the aircraft’s payload capability,
Customers had a total of 99 registered by mid-2002. Four delivered in 2000, two in 2001 and four in 2002. Law enforcement agencies flying MD 520Ns include Phoenix, Arizona (first operator; two more delivered in early 2002); Burbank, Glendale, Huntington Beach, Los Angeles, Ontario and San Jose, California; Hernando County, Florida; Orange County, Florida; Jefferson County, Kentucky, which took delivery of one in March 2002; Prince George County, Clinton, Maryland, which took delivery of two on 4 October 2000; Hamilton County, Ohio, which has seven 520Ns; El Salvador, whose Policia Nacional Civil took delivery of two in 1996; San Juan, Puerto Rico; Honolulu, Hawaii; and Calgary, Alberta, Canada. Other operators include the Tata Group of Mumbai, India, Weetabix Ltd, UK, and Belgian Gendarmerie (two). The unit cost was US$980,000 (2002).
Héli-Max Ltée from Trois-rivières, Québec, Canada was the first Canadian operator of MD520N model. They bought 6 of them.
MD 520N
Engine: 1 x Allison 250-C20R, 450 shp / 336kW
Instant pwr: 317 kW
Rotor dia: 8.35 m
Length with a rotor turning: 9.8m
Height: 2.9m
Empty wt: 1826 lb / 719kg
MTOW internal: 3350 lb, external: 3850 lb
Useful load: 800 kg
Vne: 150 kt
Max speed: 135 kts
Max cruise: 125 kts
Max range: 403 km
Rate of climb: 9.7m/s
Service ceiling: 6100m
HIGE: 9034 ft
HOGE: 5043 ft
Crew: 1
Pax: 4
Seats: 5
Fuel cap: 242 lt
Endurance @ 75%: 2 hr
All Aero 