MA - Bluebird

Eliminating the single point of failure in light aircraft

SAFETY

The MA Bluebird promises to be one of the safest light aircraft ever made.

Multiple redundancy:

With a total of 4 electric propulsion motors, 2 gas turbine generators and a small battery pack the Bluebird offers levels of redundancy previously unheard of in light aviation.

As there are 4 propulsion motors and props then there is further redundancy available. In the unlikely event one of the 4 electric motors or props fail then the Bluebird will safely continue to climb on the remaining engines and without the usual asymmetric problems that a twin suffers from.

‘No-stall’ main wing. The canard always stalls first as it has a higher angle of attack and different airfoil to the main wing. Once the canard stalls, it drops the nose and flow is reattached. The main wing never gets to a critical angle of attack. No stall, no spin.

Safety cockpit made of Kevlar for the ultimate in crash absorption and resistance to cabin penetration by outside objects.

Fuel used is Jet A-1 as it is safer, lower in cost per litre and much more widely available than AvGas.

Formula 1 style fuel tank construction. Using a bladder made from impact resistant rubber and Kevlar providing complete safety from fire in the event of an accident.

There is less workload for the pilot due to the design of the ‘Intelligent Cockpit’.

COMFORT

The layout of the entire airframe is optimised for noise reduction and ease of entry/exit for the comfort of those onboard.

Luxurious seating for 2 in the front with ‘Plus 2’ occasional seating in the rear. This area also doubles as the baggage area when only 2 are flying with the rear seats folding down to make a flat baggage tray.

Almost without exception all other light aircraft are ergonomic nightmares.

From the stepping up onto a wing, to clambering into a narrow, badly laid out and noisy cabin, light aviation has a lot to learn from the car industry when it comes to driver (pilot) comfort.

The Bluebird has an easy access cabin without any struts, wings or wheel spats to trip on or get in the way.

With oversize gull wing doors that feature a low sill height - the experience is much like entering a modern car.

Once inside, the cockpit is unusually wide, luxurious and visually ‘clean’ with it’s complete lack of switches and other dials.

A typical light aircraft has a cabin noise in cruise of 97dB.

Compare this to a typical luxury car at motorway speeds of 69dB.

As decibels are on a logarithmic scale the human ear perceives the light aircraft cabin to be about 7 times louder than the luxury car.

In this day and age this level of noise is simply unacceptable.

It creates a very tiring environment for the pilot (and passenger discomfort).

The MA Bluebird cabin will have sound levels near to that of a luxury car. 

It will do this by using a combination of double glazing on the side windows, light weight sound proofing throughout and ANR speakers that broadcast the opposite sound waves to what little cabin noise remains.

The fuel tank and batteries will also act as a sound deadening wall between the engine bay and cockpit as they take up the entire bulkhead depth.

The placement and type of engines and propellers play a big part in noise reduction. The electric propulsion motors make hardly any noise.

The propellers will be 5 bladed and very low revving (1,700rpm, made possible by being driven by electric motors) thereby reducing noise significantly.

The gas turbine engines used to power the electric generators will be well muffled and the exhaust will exit at the extreme rear of the fuselage.

All of this drive noise is behind the cabin. The props being out on the wing further reduce any cabin vibration.

The cabin will be so quiet that traditional clamping headsets will not be required. The pilot will still wear an airline style headset for comms but the passenger can relax in comfort without any headset should they wish to do so.

INTELLIGENT COCKPIT

In front of the pilot sits a simplified EFIS display - de cluttered and with only ‘percentage power’ and a fuel gauge displayed to the right of it.

All other engine parameters are monitored and as long as they fall within limits no display is given (unless the pilot requests it). If a parameter is approached or crossed then an alert appears on the main screen along with an audio warning.

In the centre console lies the main screen which is touch sensitive and primarily has navigation displayed, as well as radio and transponder frequencies, cabin ventilation & heating and various other controls.

In the highly unlikely event that the EFIS screen should fail then a backup set of mechanical gauges are available behind a ‘push and flip down’ panel immediately below the EFIS location.

Prior to flight the pilot has to pre-programme the main screen with their intended route (there is an option for ‘Local Flight’ but the endurance for this must also be given before the engines can be started). The main screen calculates the fuel required and will not allow the pilot to start the engine if there is not sufficient fuel available for the journey. 

As the main screen now has the route programmed it displays any NOTAMS en route and pre loads all the required radio frequencies. Weather information is displayed with a green, yellow and red symbol system along the route. Red being a no-go and yellow being marginal or a changing situation.

The radio and transponder are linked to the GPS navigation and preload radio frequencies and squawk codes (using voice recognition from the controllers transmissions once in flight). It is left to the pilot to simply check the code or frequency and then OK it with one push.

Once airborne, traffic alerts are also displayed on the main navigation screen.

Fuel is always ‘on’ - thereby eliminating pilot mismanagement of fuel. The intelligent cockpit monitors fuel and relates it to the flight plan on the GPS. 

SPECIFICATIONS

The Bluebird will be constructed entirely of composites. Providing smooth laminar shapes with zero corrosion or fatigue issues.

Cruise: 185 knots

Range: 700 nm +

Climb rate: 1,000 fpm

Landing speed: 70 knots

Price: Base price of £200,000 (with options available on interiors and exterior paint).

Dimensions: Wingspan 9.5m, Length 6.0m, Height, 1.8m

Cabin width: 1.7m (67 in)

Propulsion motors: 4x Siemens 40kW

Propellors: 6 bladed carbon

Generator motors: 2x Gas Turbines each generating 80kW

UPDATE

I made a scale RC model to test out the handling (and hopefully also flying) qualities of this design.

Taxi testing proved this design to be a handful to keep straight as the steerable nose wheel would get light and then the rudders were not powerful enough to overcome and differences in drag on the main wheels resulting in strong directional instability.

One attempt was made at flight (in an unsuitable area, a narrow road with high gutters, in a disused area of a new industrial estate). This one attempt resulted in a crash into the gutter and due to the high speed this resulted in big damage to the airframe. I decided at this point to terminate testing of this design as its instability on the ground was a non starter. Also with further research and thinking it became obvious that very few airfields would accommodate such a widely spaced main gear as most taxiways are too narrow for this aircraft. There is a reason all aircraft have a relatively narrow track undercarriage. But it was an interesting exercise to work through these issues and I learnt a lot from this project.