Bushby Mustang II
Updated: Oct 23, 2022
Initial Impressions: This is a hot plane built for speed!
Design Features: Two seat side-by-side aluminum monocoque kit-built with constant speed prop and a singular 8 foot plain flap (yes singular) that extends under the fuselage. This plane is designed to go fast. The low-profile top is reminiscent of a 1930s chop top Roadster and, like everything on this plane, built for speed. The cowling is long and sleek, molding effortlessly into the fuselage. The wings are short and low to the ground and the vertical stabilizer and rudder are large, giving it the control it needs to offset the relatively short wheel base and high torque.
Powerplant: Lycoming O-320 with constant speed Hartzell prop.
Ergonomics: Step over the flap, onto the wing, then onto the seat and ease yourself down into the cockpit between the sliding canopy and the windscreen bow. You have about 18 inches of clearance so keep that waist trim! The seat back angle is adjustable but you can’t slide the seat forward. The pilot’s stick is between your legs and the singular throttle, prop control and mixture are push/pull/twist style and low on the instrument panel. Constant speed props are unusual on Mustang IIs and the space for the prop control is a bit tight between the throttle and the mixture. Once I got into the Mustang II and cranked her up I was so focused on taxi, takeoff, cruise and landing, that I actually forgot to evaluate how comfortable the seat is. This tells you that I had my hands full with this plane because I’m usually highly attuned the comfort of a plane’s seat due to some chronic back issues. There is a single airliner-style vent on the right side of the instrument panel to help keep things cool once you slide the canopy closed for takeoff. Most switches are dual stacked on the pilot’s side, but this builder actually put a few switches on the wall behind the passenger’s seat. The visibility is what you’d expect from the “chop top” canopy and the saving grace is the three point attitude on the ground affords some limited forward visibility.
Start/taxi/takeoff: Start is easy. Once complete, start throwing switches to get everything powered up! This particular MII has a lot of equipment to go with all the switches. The equipment includes a JPI fuel flow meter, Dynon D-10A, two Narco Mk-12D dual nav/comm, Dynon EMS, Bendix King Skymap 2C, and TS autopilot. On the taxi you will feel every crack in the asphalt and every concrete expansion joint due to the solid rubber tailwheel. After run-up, slide the canopy forward, lock all three canopy locks, line up on the runway and get ready! Feed in right rudder as you advance the throttle. Lift the tailwheel slightly but don’t push over to a level attitude because the P-factor will get you a little more of a look at the runway edge lights than you’d like. Keep the Mustang in the slightly nose high attitude and it’ll fly away when ready.
Climbout: Climbout is fast! The Mustang II’s VSI registered a 1500 fpm climb-out all the way to 6,000 feet and showed no signs of slowing down. Climb between 120-130 mph to keep the cooling air going down those intakes. Robert Bushby designed this plane for speed and the air intakes take into account all the best efficiencies of fluid dynamics. Bottom line: go fast to keep things cool under the hood!
Cruise: At 6,000 feet the MII produced about 165 mph indicated airspeed (186 mph true a/s) with the manifold pressure at 2300 inHg and 2,400 rpm. Down low (1,500’) at 25/25, the Mustang brought 175 mph indicated!
The Mustang II, as tested, did not have any stall warning device installed; nor did it produce a stall buffet before crispy breaking in nose-down pitch with right wing drop-off at precisely 65 mph. With the flap extended to any position the stall speed does not change more than 1 mph, clearly making the flap a drag-inducing device, allowing for steeper approaches with some power on.
At all cruise speeds, pitch and roll are very stable, with roll stability increasing with airspeed. The yaw stability was not nearly as stable and tends to oscillate without steady rudder input. New Mustang II pilots should practice “rolls on a heading” to get a feel for the natural Dutch Roll tendency of this plane.
The plane is equipped with electric pitch and aileron trim with lighted visual indicators on the center console. The builder of this particular MII designed a unique “Master Arm” flap power switch on the center console which requires the guard cover to be lifted and the switch to be armed before power is applied to the flap control switch. The flap control switch is hidden on the left side of the center console and is slightly awkward to depress as it is located outside of the pilot’s right thigh. The idea for the guarded power switch and awkwardly placed flap switch was to prevent inadvertent extension while trying to trim the elevator or ailerons.
Approach and landing: There is not much to the approach other than planning ahead to get the aircraft slowed down. Initial landing practice was accomplished on a 5,500 ft runway and I took at approach speed of 85 mph (1.3 x Vso). This speed, coupled with the flap deployed to 40°, produced a very comfortable power-on approach, but the Mustang II floated considerably in the flare, especially when accomplishing a three-point landing. Subsequent approaches were at 80 mph and 75 mph. The 75 mph approach obviously produced the least time in the flare but the visibility on the approach was not as good over the long nose. Additionally, the curved Plexiglas on the left side of the windshield creates some visual distortion and makes you wonder if your eyesight is deteriorating. The reminder of the stall characteristics and lack of stall warning demanded attention at this speed. The approach back at home field (2,500’ rwy length) was accomplished at 80 mph and resulted in a landing distance of less than 2,000 feet, even with moving targets on short final (a busy road with the occasional 18 wheeler).
If executing a three point landing, once the plane is securely on deck, stay quick on the rudder pedals. With the stick planted firmly aft, the tailwheel, along with the large rudder, provides plenty of positive directional control. Wheel landings produce better initial control. After some deceleration, gently lower the tail, then firmly plant it with full back-stick. Between about 30-40 mph, the pretty lady will want to dance! Have your dancing shoes ready and use small and quick pedal inputs while maintaining full aft stick to keep the Mustang going the right way down the runway. Use brakes only when the speed is low. Toes should be checked at the bottom of the pedals before landing.
Wrap-up: The mission of this plane is speed which it does with sleek style. It is a lot of airplane and therefore probably not for the novice pilot or the low-time taildragger pilot. Like it’s namesake, the North American P-51 Mustang, it looks and sounds good, and when well-handled, will make her pilot look good.