Photograph:
McDonnell Douglas 520N ZK-INR (c/n LN-009) at Hastings, New Zealand in April 2012 (David C Eyre)
Country of origin:
United States of America
Description:
Five-seat light utility helicopter
Power Plant:
One 317 kw (425 shp) Allison 250-C20R turboshaft
Specifications:
- Rotor diameter: 8.33 m (27 ft 4 in)
- Length: 9.78 m (32 ft 1¼ in)
- Height: 2.74 m (9 ft)
- Rotor disc area: 54.51 m² (586.8 sq ft)
- Max speed at sea level: 281 km/h (175 mph)
- Max cruising speed at sea level: 249 km/h (155 mph)
- Max rate of climb at sea level: 564 m/min (1,850 ft/min)
- Service ceiling: 4,320 m (14,175 ft)
- Range at sea level: 402 km (250 miles)
- Endurance at sea level: 2 hrs 24 mins
- Empty weight: 742 kg (1,636 lb)
- Loaded weight: 1,519 kg (2,350 lb)
History:
In January 1988 McDonnell Douglas Helicopter Company announced its intention to develop a version of the MD-500 series using its NOTAR (no tail-rotor) anti-torque system, with the first aircraft to fly in May 1989. In the event the schedule slipped a little, and the first prototype known as the MD-530N (N530NT) flew on 29 December 1989, first flight of the MD-520N (N520NT) taking place on 1 May 1990, the first production MD-520N flying on 28 June 1991, later being delivered to the Phoenix Police Department in Arizona. In September 1992 a MD-520N set a Paris to London speed record of 1 hour 22 minutes 29 seconds.
Certificated in more than 20 countries, the MD-520N is known as the Defender in its military guise, being developed for the US Army as the MH-6J. Roles for the series include a variant for fire-fighting, using 341 litre (75 Imp gal) Bambi buckets. The NOTAR system provides an anti-torque and steering control without an external tail rotor, this eliminating the danger of tail strike, air emerging through Coanda slots and steering louvres being cool and at low velocity. Power plant is the Allison 250-C20R de-rated to 317 kw (425 shp), providing 280 kw (375 shp) max continuous, and accommodation is provided for five.
First of the series seen in this region was ZK-HMD² which made a demonstration tour of New Zealand before going to Queensland where it became VH-NTR (c/n LN-045) with Horizon Helicopters. It later became ZK-HZG. A further machine arrived in February 1999 as VH-FLY (c/n LN-009 – ex N1608S), which later returned to the US as N809M. Eventually in late 2004 it arrived in New Zealand and commenced work with Heli-Flight of Masterton as ZK-INR. A further example was registered in New Zealand in mid-2006 for Faram Helicopters of Gisborne, becoming ZK-HWH (c/n LN-098), this being a 2002 production machine which had seen service with the City of Phoenix Police Department.
Total production of the MD-520N series has been 111 aircraft of which 25 examples have over the last 10 years been registered in New Zealand, and further examples have been imported to be placed on the register. Further registrations include ZK-IJW (c/n LN-016), ZK-HEN (c/n LN-019), ZK-IEN (c/n LN-047) ; ZK-IDZ (c/n LN-046); ZK-HBC (c/n LN-018); ZK-HCZ (c/n LN-106); ZK-HDN (c/n LN-080); ZK-HDW (c/n LN-072); ZK-HFJ (c/n LN-027); ZK-HHY (c/n LN-058); ZK-HQP (c/n LN-093); ZK-HUL (c/n LN-059); ZK-HWH (c/n LN-098); ZK-HYY (c/n LN-107); ZK-III (c/n LN-089 – ex N272BP, N52038), later exported; ZK-IJF (c/n LN-053), later exported; ZK-IPR (c/n LN -109); ZK-IRS (c/n LN-065); ZK-ISG (c/n LN-038), later exported; ZK-ISO (c/n LN-006); ZK-ITX (c/n LN-070) and ZK-IDB (c/n LN-022 – ex OY-HEP). New Zealand operators have included Mt Hutt Helicopters, Alpine Hunting Adventures, and Garden of Eden Helicopters.
In April 2015 two examples were imported to Australia for Gunn Resources Pty Ltd of Newon, QLD, these machines becoming VH-EPJ (c/n RN032) and VH-EPY (c/n RN034) on 24 April; and another example became VH-INM (c/n LN089) also owned by Gunn Resources, being operated by Rotor Force of Woodford, QLD before being cancelled from the register in November 2017. MD-520N VH-MYR (c/n LN026) was exported to the United States in October 2017.