Developed from coaxial twin-rotor B-1 by Newby Brantly, the B-2 with single main rotor and anti-torque tail rotor configuration first flew on 21 February 1953. An improved second prototype flew on 14 August 1956. This was to enter production in 1958 receiving FAA certification on 27 April 1959.

A total of 194 B-2s and 18 B-2As (with additional headroom) were produced between 1960 and 1963 and the improved Model B-2B with metal rotor blades and fuel-injected Lycoming IVO-360-A1A engine was certified on 1 July 1963. A total of 165 were built between 1963 and 1967 (the company owned by Gates Learjet from 1966).

Type certificates for the Brantly Bs were purchased in 1971 by Michael Hynes and revised as the 2 H2/YHO 3BR.
Michael K. Hynes established Brantly-Hynes Helicopter Inc. on 1 January 1975, initially to provide product support for the large number of Brantly helicopters in use.
He subsequently started up a production line for the B-2B and built one (as H-2) in 1975, and also the larger Model 305. James T. Kimura was the third owner of the B-2 type certificate, and delivered his first B-2B on 25 August 1990.
Brantly Helicopter Industries (BHI) took over manufacturing and marketing rights and production facilities in 1989 with three were built under this name, which received the FAA production certificate on 19 July 1996. The first new-build B-2B (N25411 c/n 2001) was flown on 12 April 1991. In 1992, a B-2B cost US$120,000 to US$135,000 depending on equipment fit.
On 23 December 1994, Brantly International obtained the type certificates for the Brantly B-2B and 305 helicopters from Japanese-American businessman James T Kimura’s Brantly Helicopter Industries, which had acquired them in May 1989. In 2002, Brantly employed 40 in its 2,790 ha facility. By 2002, Brantly Helicopter Inc of Vernon, Texas were again producing the B2B.

British Executive Air Services had acquired a production licence for the B-2.
In 2003 the cost was US$170,000 basic equipped.

A relatively simple design, with blown main transparency and constant-taper fuselage. Double-articulated three-blade main rotor with pitch-change and flapping hinges close to hub and flap/lag hinges at 40% blade span; symmetrical, rigid, inboard blade section with 29% thickness/chord ratio, outboard section NACA 0012; outer blades quickly removable for compact storage; rotor brake standard; two-blade tail rotor mounted on starboard side, with guard. Transmission through automatic centrifugal clutch and planetary reduction gear. Bevel gear take-off from main transmission, with flexible coupling to tail rotor drive-shaft. Main rotor/engine rpm ratio 1:6.158; tail rotor ratio 1:1. Main rotor minimum speed 400 rpm; maximum 472 rpm.
Conventional and manual controls; small fixed tailplanes on port and starboard sides of tailcone. A semi-monocoque fuselage with alloy-stressed skin. Inboard rotor blades have stainless steel leading-edge spar; outboard blades have extruded aluminium spar; polyurethane core with bonded aluminium envelope riveted to spar. All-metal tail rotor blades. Fixed skid type landing gear with oleo-pneumatic shock-absorbers; small retractable ground handling wheels, size 10×3.5, pressure 4.12 bar; fixed tailskid. Optional inflatable pontoons attach to standard skids for over-water operation. One 134kW Textron Lycoming IVO-360-A1A flat-four air-cooled piston engine, mounted vertically. Fuel contained in two interconnected bladder tanks behind cabin, total capacity 117 litres of which 115 litres are usable. Oil capacity 6.9 litres. Two seats, side by side in enclosed cabin; forward-hinged door on each side. Dual controls and cabin heater standard. Ground accessible baggage compartment, maximum capacity 22.7kg in forward end of tailcone.

In 1959 the Army procured five examples of the Brantly Model B-2 light helicopter for evaluation in the observation role. The five machines obtained by the Army (serials 58-1492 through -1496) were designated YHO-3 and tested at both Fort Rucker and the Naval Air Test Center at Patuxant River, Maryland. The aircraft was ultimately judged to be too small to be of practical military use and all five examples were eventually returned to the manufacturer.

B-2
Engine: Lycoming 135 hp
Rotors: 3-blade main 2-blade tail
Rotor diameter: 23 ft
Loaded weight: 1,250 lb
Seats: 2

B2B
Engines: Lycoming IVO-360-A1A, 180 hp,134kW.
Main rotor diameter: 7.24m
Fuselage length: 6.63m
Height: 2.06m
Disc loading: 3.7 lb/sq.ft.
Pwr loading: 9.3 lb/hp.
Max TO wt: 1670 lb / 757kg
Empty wt: 1032 lb / 463kg
Equipped useful load: 576 lb.
Payload max fuel: 390 lb.
Range max fuel/ cruise: 152 nm/1.8 hr.
Range max fuel / range: 196 nm/ 2.3 hr.
Service ceiling: 12,500 ft / 3290m
Max speed: 161km/h
Max cruise: 87 kt / 145km/h
Max range cruise: 87 kt.
ROC: 1400 fpm.
HIGE: 4300 ft.
HOGE: 2500 ft.
Max sling load: 400 lb.
Fuel cap: 186 lb.
Seats: 2.

2 H2/YHO 3BR
Engine: Lycoming IVO-360-A1A, 180 hp.
TBO: 900 hrs.
Main rotor: 23.7 ft.
Length: 28 ft.
Height: 6.8 ft.
Max ramp weight: 1670 lbs.
Max takeoff weight: 1670 lbs.
Standard empty weight: 1069 lbs.
Max useful load: 601 lbs.
Zero fuel weight: 1490 lbs.
Max landing weight: 1670 lbs.
Max sling load: 400 lbs.
Disc loading: 3.7 lbs/sq.ft.
Power loading: 9.3 lbs/hp.
Max usable fuel: 183 lbs.
Max rate of climb: 1330 fpm.
Service ceiling: 12,500 ft.
Hover in ground effect: 4,300 ft.
Hover out of ground effect: 2500 ft.
Max speed: 87 kts.
Normal cruise @ 3000 ft: 78 kts.
Fuel flow @ normal cruise: 72 pph.
Endurance @ normal cruise: 2.4 hr.
Seats: 2.

Brantly B-2B
Engine: Lycoming IVO-360, 180 hp
Rotor span: 7.24 m
Blade area: 0.203 sq.m
MAUW: 757 kg
Empty weight: 463 kg
Max speed: 161 kph
Cruise speed: 145 kph
Climb rate: 9.6 m/s
Seats: 2