In 1961, with thoughts of reviving a pre-war name for the jet replacement to the Dove, the 125 was originally billed as the de Havilland Jet Dragon in the early sixties. Designed specifically for the business aircraft category, the DH 125, accommodates a crew of two and from six to twelve passengers. The first of two prototypes flew on 13 August 1962, as the DH.125, with Rolls-Royce Viper 20 engines producing 1350kg of thrust each. The first production aircraft had a 0.9m greater wingspan and 1.2m longer fuselage as well as Viper 520 engines.

The original DH 125 was marketed by de Havilland, Hawker Siddeley, Beechcraft-Hawker and finally British Aerospace.

In 1963 the DH.125 was to be sold in the US by Atlantic Aircraft Sales Corp and AiResearch Aviation Services for a fully equipped price of US$740,000.

In 1965 Hawker Siddeley’s DH 125 flew one-stop from Wilmington, Del. To Los Angeles in 6 hr 50 min against headwinds of 110 mph following a 17 day US tour during which it made 107 demonstration flights. IIt flew at 35-39,000 ft with one stop at Wichita, Kan. AiResearch, the US distributor had the basic price at $575,000 and completely equipped at $750,000.

The original DH 125 evolved through the 1A, 3ARA, to the 400 Series.

Twenty Srs.2s were equipped as Dominie navigation trainers for the Royal Air Force.

The more significant changes took place from the advent of the 400 series. It was at this point that the Beech Aircraft Corporation took over the marketing of the 125 in North America between 1968 and 1972. The Series 400, since 1970, was marketed in the United States as the Beechcraft Hawker BH 125. It featured a centre cabin aisle recessed below the level of the floor supporting the seats on either side. This gave sufficient cabin height to allow a passenger stand-up headroom.
Their big contribution was a major improvement to the cockpit layout and ergonomics of the 400. The 600 series saw a two foot extension to the fuselage with corresponding benefits in passenger appeal. and first flew on 21 January 1971. The 700 series brought the switch from straight jet Viper power to the fanjet power of the Garrett TFE 731-3.

Hawker Siddeley continued to build the jet in Great Britain, but its agreement with Beech was terminated in middle of 1975.
Continued development of the BAe 125 led to the Srs 800, which made its first flight on 26 May 1983, and the BAe 1000. The BAe 125-800 is an extensively revised development of the earlier -700 series, featuring more powerful engines (two Garrett TFE731-5R-1H turbofans) and new longer span outboard wing sections. Capable of 533 mph maximum cruising speed, the -800 has an economy cruise of 461 mph at 40,000 feet over 3454 miles (5560 km). Latest state of the art aerodynamic design theory has been incorporated in the 10 foot outboard wing panel, increasing the span by 4 foot 4½ inches. Fuel tankage has increased from 9440 lbs to 10,000 lbs with a corresponding increase in NBAA VFR range from 2660 nm in the 700 to 3000 nm in the 800 model. Digital autopilot and avionics allow the 800 to join the “glass cockpit” group. Numerous other 800 improvements include a new acrylic windshield, deletion of the ventral fin, nose wheel doors closed when gear down and architectural changes in the cabin area giving increased width and height.

 

By 1985, 585 DH125 derivatives had been ordered.

Hawker 800XP

The series 800 Hawkers were built in the UK until Raytheon purchased the production rights from Hawker Siddeley in 1993, and two years later the 800XP went into service. Over 1,000 of both models flying. The 800XP got an interior upgrade in 1999. Pilots got the Honeywell SPZ 8000 avionics suite or can choose the Rockwell Collins EFIX-86 system as an option. The Hawker 800XP has been extremely well received for fractional aircraft ownership programs, as well as finding service with the U.S. Air Force, the Republic of China and in Japan.

After the purchase of the BAe Corporate Jets division by Raytheon, the BAe 125-800 was renamed the Hawker 800, and the BAE 125-1000 renamed the Hawker 1000. Hawker 1000 variant production ended in 1998.

The Japanese Air Self Defence Force have selected three BAe 125-800s for flight inspection duties in 1989, the first time in the history of the JASDF that a non-American, foreign-built aircraft has been ordered. These were designated U-129As.
Orders exceed 187 by 1990, in addition to 573 of earlier versions, and the USAF took delivery of six BAe 125-800s, designated C-29A, for flight inspection duties in 1989.

In 1996, production was transferred to United States. 

HS125 Srs 400
Engines: Two 3,360 lb (1,525 kg) st Rolls-Royce Bristol Viper 522 turbojet.
Wing span: 47 ft 0 in (14.33 m)
Length: 47 ft 5 in (14.45 m).
Wing area: 353 sq ft (32.8 sq.m).
Gross weight: 23,300 lb (10,568 kg).
Max cruising speed: 510 mph (821 kph) at 31,000 ft (9,450 m).
Typical range: 1,762 miles (2,835 km).
Accommodation: 12 passengers
Crew: 2

DH125-600
Engines: 2 x Rolls-Royce Vi-per 601 turbofans, 3,750 lb.
Wing span: 47 ft 0 in (14.33 m).
Length: 50 ft 5.75 in (15.39 m).
Height: 17 ft 3 in (3.51 m).
Max TO wt: 25,000 lb (11,340 kg).
Empty wt. 12,700 lb
Max level speed: 345 mph (555 kph).
Stall 94 mph
Initial climb rate 4,500 fpm
Ceiling 41,000 ft.
Fuel cap: 9,450 lb.
Max range 45min res: 1,570 nm.
Max operating speed: 345 mph (555 km/h) IAS.
Takeoff distance (50') 5,350 ft.
Landing distance (50') 2,550 ft.
Seats 9

BAe125-700
Engines: 2 x Garrett TFE 731-3R, 3700 lbs thrust.
Seats: 8/14.
Length: 50.8 ft.
Height: 17.6 ft.
Wingspan: 47 ft.
Wing area: 353 sq.ft.
Wing aspect ratio: 6.3.
Maximum ramp weight: 25,000 lbs.
Maximum takeoff weight: 24,800 lbs.
Standard empty weight: 13,700 lbs.
Maximum useful load: 11,300 lbs.
Zero-fuel weight: 16,050 lbs.
Maximum landing weight: 22,000 lbs.
Wing loading: 70.3 lbs/sq.ft.
Power loading: 3.4 lbs/lb.
Maximum usable fuel: 9450 lbs.
Best rate of climb: 3000.
Certificated ceiling: 41,000 ft.
Max pressurisation differential: 8.4 psi.
8000 ft cabin alt @: 41,000 ft.
Maximum single-engine rate of climb: 1350 fpm @ 195 kts.
Single-engine climb gradient: 415 ft/nm.
Single-engine ceiling: 21,600 ft.
Maximum speed: 450 kts.
Normal cruise @ 37,000ft: 428 kts.
Fuel flow @ normal cruise: 1450 pph.
Stalling speed clean: 119 kts.
Stalling speed gear/flaps down: 83 kts.
Turbulent-air penetration speed: 230 kts.

BAe125-800
Engines: 2 x Garrett TFE 731-5R-1H turbofans.
Max cruise: 533 mph.
Economy cruise: 461 mph at 40,000 feet over 3454 miles (5560 km).
Pax cap: 14.

Hawker 800XP
Engines two 4,669-lb. Honeywell TFE731-5BR turbofans
Gross wt. 28,120 lb.
Empty wt. 16,245 lb.
Fuel capacity 1,492 gal
Max cruise 447 kts
Long range cruise 402 kts
Range 2,285-2,621 nm.
Ceiling 41,000 ft
Takeoff distance 5,030 ft
Landing distance 2,650 ft
Seats 8-15

Hawker Siddeley HS 125 Dominie T. Mk 1
Engine : Bristol Siddeley Viper 301, 13342 N / 1360 kp
Length : 47.408 ft / 14.45 m
Height: 16.503 ft / 5.03 m
Wingspan : 47.014 ft / 14.33 m
Wing area : 352.952 sqft / 32.79 sq.m
Max take off weight : 21201.1 lb / 9615.0 kg
Weight empty : 11404.3 lb / 5172.0 kg
Max. speed : 435 kts / 805 km/h
Service ceiling : 41011 ft / 12500 m
Wing load : 60.07 lb/sq.ft / 293.0 kg/sq.m
Range : 1477 nm / 2736 km
Crew : 2