From The Cockpit – Grumman Cougar

Standard empty weight of the Cougar is about 2,530Ib; with a MTOW of 3,800Ib, this allows a full fuel payload of about 600Ib, enough for three adults with baggage; the large fuel tankage however permits excellent versatility – topped off at 90US gal, four adults and baggage can be hauled for six hours total endurance, an IFR range of 640nm.

In short, the Cougar is a well capable yet basic aircraft, with the simplest but nevertheless effective of systems fitments. Pilot and crew comfort are good, as are ventilation and the heater (engine exhaust muffs) system.

The GA7 was developed at the time when four seat ‘twins’ became a fashionable configuration on the GA market. Beech was there with the Duchess, Piper also, with the Seminole and Aircraft Designs (Bembridge) on the Isle of Wight was trying it on with the Sheriff, a design owing a lot to the Miles’ formula, a generation before. Whilst the Sheriff didn’t make it, the Duchess, Seminole and Cougar did. There is clearly something in the formula, for recently, against orders Stuart Miller has put the Seminole back into production. For air taxi/charter four seat twins don’t go far, but they make good multi engine and IFR trainers and as well, are versatile personal transports for the budget conscious owner/pilot who appreciates engine redundancy.

Gulfstream based the design variable quite differently to both Beech and Piper.

The Cougar can reasonably be described as a ‘minimum’ power twin and yet has a very comfortable cabin and excellent baggage volume. The internal dimensions provide for very relaxed elbow room and leg stretching room for the rear pax. The greater frontal area quite simply adds to aeroplane drag, in spite of the fuselage and nacelle lines being right (the nacelles in particular cowl the engines very sleekly, to me reminiscent of the Twin Commanche 0-320 installation). Engine-out, the Cougar has one 0-320 to haul it through the air; this means undoubtedly, that GO on an engine failure after takeoff (EFATO) is a dicey situation. My view of the safety conditioning in this case is that the pilot should brief to put it down in an emergency, unless conditions are well above marginal (in the form of low pressure altitude, air temperature, light weight, nil wind shear, etc); accepting that position (mostly the case in the Australian climate) means the Cougar is a non-goer, EFATO, and the limitation is faced; this limitation is one which I feel is definitely worth living with in the case of the Cougar.

Of course I have been talking broad brush; the Cougar Manual is comprehensive and lays down all the figures for one engine climb performance. Near sea level/lSA, with half fuel and 3 on board without baggage, it performs adequately on one engine, demonstrating a rate of climb (AOC) of about 300ft/min.

If such a takeoff emergency briefing makes the EFATO operation of the aircraft acceptable, then normal operation can only be described as efficient, if not fast. A 65% power cruise speed of 140 knots TAS is significantly less than that of high-performance singles, but for a total fuel consumption of 15US gal/hr the specific air range (SAR) approaches 10nm/US gal, excellent for a twin.

There are few surprises in the walk around about the Cougar.

For a complete check of the stall warning system, consisting of two leading edge warning vanes on the left wing (one for flaps UP and the other for flaps DOWN, the appropriate vanes being automatically switched in and out according to the wing flaps position), two checks need to be carried out. Fuel is contained simply in two tanks, integral interspar, or in each wing. Total usable capacity is 114US gal. The landing gear design is straight oleo type; nosegear is fully covered when UP, mainwheels remaining exposed in their wheel housings. Down at the tail, rudder operation can be checked: this is because of the rudder control circuit containing springs (more on this later). It is a criticism of the aircraft that the rudder bar gust lock, which locks the rudder pedals centrally, is simply not adequate in preventing substantial rudder swinging and banging on the stops in a gusty tail or quartering wind on the ground, when the aircraft is parked. As with many other types, a rudder gust lock is required.

The engine installations have cowl flaps. Engines with slight oil leaks have the tendency to result in an oil trail dribbling along and off the engine exhaust stacks (doesn’t seem to cause smoke!) The internal trim of the Cougar is of a good standard, particularly the seat upholstery. The ergonomic arrangement from the driving seat is satisfactory. Landing gear control and annunciation positioning is excellent. Fuel selectors are on the fuel control panel between the seats, uncomfortably close to seat belt buckles and thus inadvertent hand movements; the selectors shouldn’t be knocked accidentally to OFF however, because that position is guarded for each of them. Flap travel rate is low, almost too low as the control is not preselect but continuous and must be held down to lower the flaps. Emergency landing gear extension is effected by extension of a singular control knob, which mechanically releases the gear unlocks.

Visibility is good but for the hoop type overhead frame at the front of the cockpit having thick windscreen stanchions.

The 0-320s are carburetted: nothing fancy, and each has an electric primer for starting assist. The checklist at START calls for the Left Mag (impulse-coupled) only to be on; in fact it is my experience that smoother starts are often accomplished by having both Mags on before engaging the starter.

The Cougar is pleasant and stable in flight. Nevertheless, all three of the flying control circuits have springs in them, indicative that along the development path the handling qualities of the Cougar had been deficient against the airworthiness requirements: the elevator circuit has a hefty downspring, most likely in order to assist static longitudinal stability at low speed/high power, the aileron circuit has a centring spring, probably to aid lateral stability but which doubles as a lateral trimmer (bias action); the rudder cables have a restoring spring and the feel of the nosewheel steering NWS, but do tend to mask directional feedback on the ground. Further, for tight manoeuvring differential braking is a necessity (although this does result in an excellent turning circle – about one mainwheel). On the takeoff roll, the best technique I find with the Cougar is to open to about 2,000rpm prior to rolling; opening from near idle results in a yawing moment which cannot be held against the springs and pedal stops, requiring differential braking to maintain directional control initially; this is not necessary with the former technique.

A good liftoff speed is 75 KIAS (flaps UP for a normal takeoff); 7 degrees noseup gives a reasonable acceleration through a blueline speed of 85 KIAS to a climb speed of 96 KIAS, which I find comfortable. Elevator control force to rotate and liftoff is substantial, in part due to the flapless configuration. Pitch trim change on gear retraction is negligible, whereas there is a significant trim change on flap extension to 10 degrees. Pitch control is positive without being overly sensitive. Pitch trim is effective; once trimmed precisely the Cougar holds attitude steadily. Lateral control is light, almost touchy: this means two things – firstly attention to heading maintenance must be given during instrument approaches, but secondly, only a light pressure is required to keep the wings level in light turbulence or to recover heading after wandering off when pilot attention is drawn elsewhere. On the other hand Dutch Roll is easily excited; the rudder is light and care needs to be taken to prevent further excitation of the oscillation by incorrectly ‘phased’ dabs on the pedals. In smooth air, the Cougar can be trimmed to fly steadily hands off. The Cougar’s blueline speed is 85 KIAS, appropriate to a pitch attitude of about 7 degrees. Engine-out, rudder pedal forces prior to trimming are not overly heavy.

On approach, or in the circuit, the high LG and 1 O deg flap extension speed of 146 KIAS assist in making arrivals flexible in a high traffic density environment. A reasonable final approach speed in 85 KIAS down to decision height and then· a gradual speed reduction on selecting full flap, to 70n KIAS at the threshold. The elevator maintains its ‘bite’ to quite low speed, so that only a gentle touch is required in the flare. From the final full flap attitude the pitch change to a ‘mainwheels-touchdown’ attitude is quite substantial (think, the nosewheel is never too high, or a nosewheel touchdown is likely to occur).

That then is flying the Cougar. Not a common aircraft, but should you find one on the ‘lot’, (and several more have been imported recently) it is definitely worth a close look. By virtue of its cabin size and layout, as personal transport it has more than others of its ilk to offer.