Rockwell’s Rover

With still only a handful of Rockwell Commander 114s in Australia, and reinforcements arriving but spasmodically, the opportunity to evaluate one of these medium-priced four-place types knocks sparsely.

The Rockwell Commander 114 is undeniably a professionally designed aircraft; some call it a sexy beast, others look at it and utter superlatives; still others accept it as an ideal touring/IFR/small corporate steed.

Somewhere in its design lurk echoes of the much-beloved North American Mustang, the Mitchell, and the Bronco for the marriage some years back of North American and Rockwell Standard resulting in Rockwell International retaining much of the old North American design team, and techniques.

Rockwell International has already amassed much expertise in the supersonic and combat field; the Vigilante, the X-15, engines for the Saturn V rocket, and the Apollo command module, to name a few successes.

And of course, there is a long, proud line of twin-engine light aircraft types bearing the old Aero Commander prefix. To fly one of these is often accepted by many pilots as being the benchmark of achievement.

The Rockwell International singles’ initial arrival in Australia wasn’t an instant success; the little 112A was a brave entrant but short on both power and range. Its big-aircraft engineering and undeniably superb pilot and passenger comfort were not enough to satisfy the money-spenders who wanted more engines and longer legs for their money.

By the time the 114 landed in this country, much harm had been done, verbally and by rumour. It took distributors and dealers a lot of hard work and practical proof to lay the hearsay reports, but they’ve succeeded and now the queue of potential buyers is growing – but the list of Rockwell 114s arriving seems to be dwindling at this stage, with demand growing in the source nation (USA) and in the European theatre.

Those lucky enough to secure a 114 are getting what they really want – luxury four-place within, a steady aircraft which combines as an excellent instrument platform, and reasonable range without sacrificing too much payload for fuel.

Sitting in a unique place in the higher-powered four-place singles market, the 114 boasts two undeniable attributes – style and quality. Add to that a long list of creature comforts (including an enviable 47in cabin width) and you have an aircraft hard to beat in many respects.

The latest variant of the 114 is the GT (Gran Tourismo) which has an extra prop blade, basically the same airframe as the standard 114, a slightly higher AUW – and a lot of cosmetics built into the new package.

Big-aircraft engineering is apparent in the 114 now flying throughout Australasia, which means an aircraft for all seasons.

The 114 is a medium-to-long-legged beast, if one adopts anything but a dogmatic attitude to the range-payload equation, and AADR knows from experience on the type that long legs are things of ease and relaxed comfort in the Rockwell product.

The cruciform tail, perhaps unique in the Ttail/ conventional empennage market, helps a lot in this respect. Circuit work is likewise a matter of ease, with the actual touch phase aided by a big trailing beam undercarriage taken directly from the Bronco type.

Engineered to surpass the rigid FAR 23. 7 safety standards, the 114’s fuselage is built into three main sections – from prop boss to firewall, firewall to aft cabin, and aft cabin to the back end.

The centre wing structure is engineered to the fuselage in such a way as to absorb part of the wing torque; wings are made of stressed skin metal and incorporate main tanks.

Rockwell Commander 114 serial 14276 – originally identified November 4956 Whisky and bearing Australia tradeplate letters VH-IBA for our test flight – was made available for evaluation by Eastern Commander managing director Captain Frank Owen, operating out of Bankstown.

A full evaluation including all permissible manoeuvres and a brace of touch and go’s at Hoxton Park proved all claims made in Rockwell international glossy brochures. It also proved the point that in the 114 one has an aircraft built to last, which fully justifies the initial outlay – in this case $60,000 which included a very respectable panel and avionics.

The 114’s distinctive cruciform tail and slab-sided appearance make it a head-turner no matter where one lands. Despite the appearance of carrying a deal of built-in side windage, the Rockwell 114 is, as our back-seat passenger put it succinctly, a sexy aeroplane.

It has a classic European look about it – if that remark is understood by readers. Subsequent testing proved performance to be just as sparkling and alive as looks.

We carried two back-seaters on this evaluation, putting us not far under gross with full tanks, and nil baggage. Gross is carded at 2800Ib (Utility cat).

Static evaluation, concentrating mainly on the cabin area, proved eminently satisfactory. Rear-seat passengers have ample leg room, ventilation, visibility and (after engine start) low decibels.

From the pilot’s point of view, the seating, panel, control access and fuel management arrangements could not be bettered, such is the design thought input in the product.

A walk round prior to start-up disclosed much of the big aircraft thinking in the overall design; a beautifully-cowled Lycoming six-cylinder 10-540-T4BSD driving a twin-blade constant speed Hartzell; overall finish to airframe and wings; big trailing beam main legs; easy-drain points for the main tanks, and other points in the 114’s favour.

From the outside, the Rockwell 114 sits – to use descriptive words – wide and fast. Inside, via port or starboard doors and an easy-access walkway, the aircraft is obviously tailored around the 300-odd people of assorted shapes and sizes that Bethany invited to sit in the initial mockup.

The cabin is virtually four separate seating areas, divided by central consoles or armrests, such is the room within the beast.

The panel; all primary and supporting flight instruments are located on the main panel’s left side, engine and fuel system gauges on the left sub-panel, with avionics; ve. nt controls and circuit breakers located on the main instrument and sub-panel’s right side.

Front section occupants are held in place by an inertia reel system, with the shoulder straps retracting into the seat back when not in use. Aft of the rear seats lurks a 200Ib limit baggage compartment, easily accessible via an all-metal door port side aft.

A final word on the structure overall before engine start; Bethany claims a safe life qf wing and associated structure of 38 years, a fail-safe elevator system, the ability to pass S0ft/sec gust loads in flight, and landing gear and doors capable of withstanding yaw loads up to 1. 6Vs with nil flap.

Start drill for the big Lycoming; mixture to Idle Cut-Off, fine pitch, throttle cracked ¼in, Master on, and fuel pump on until a pressure indication registers. Then mixture to rich for a moment before retarding to Idle Cut-Off, and fuel pump off. Fire up, and when the engine catches go to Full Rich set throttle to between 800-1000rpm, and switch on the alternator.

With the Lycoming working, it’s obvious that Rockwell International has done what it claims – got to the decibel reduction problem at the source. Bethany has come up with a noise-deadening engine muffler which was proved during this evaluation not to affect engine output; the front windshield thickness has been increased from 3/16 into ¼in, and pads of soundproofing insulation sit in the firewall, doors, side panels, the overhead and floor.

All this adds up to a quiet aircraft.

Optional fitting for the fastidious includes more soundproofing in the shape of two 1/8in panes with ¼in airspace between!n them in door and side windows.

Waddle and Shimmy got full marks on our checklist for nonexistence. The turning circle on the ground was proved to be the claimed 21ft 10in, and low foot loads were assessed during the taxi out to the holding point.

Back-checking with rear seat passengers during run-out, access, visibility, legroom, air supply, seating and noise levels all got Above Average or Excellent markings on the checklist. These markings were either sustained or surpassed during the subsequent evaluation – and AADR’s passengers are pros at the checking and constructive criticism game.

Runup at the holding point is standard drill; controls, trims (a whiff of right rudder helps for the take-off run, with elevator trim tending towards the back end of the Take-off range); mag drop check at 2000rpm, two prop-cycling exercises (our own habit), slow-running check at 600-700rpm, then return to 1000rpm.

Ten degrees of flap were selected (flap lever, like so many other types, is on the console’s far side as far as the driver is concerned), cowl flaps shut, and Outside Air Temperature (OAT) checked at + 14C, negligible wind, before turning on and flicking ON the fuel pump.

At full power (260hp at 2700rpm), the test aircraft accelerated briskly, being allowed to assume a natural stance giving a slight angle of positive incidence as speed built up to the recommended Vr of 65kts IAS. Rotation was achieved at 70kts IAS with slight but definite right rudder pressure fed in to help trim.

(Manual figures list 69kts IAS as Vr and liftoff, with a climb speed of an initial 72kts IAS).

Control response was instantly delightful and obedient; cycling the undercard (From green lights on to all lights out, via a red “Cycling” warning on the glare shield annunciator took above five seconds with minimal pitch change thanks to the cruciform tail assembly) and retracting flaps, the classic 24/24 settings were applied.

A satisfying climb figure of better than the carded 1088fpm was logged, with about 94kts IAS showing, all temperatures normal and cowl flaps still shut. Maximum performance climb means setting up max power and 2700rpm, climbing at 91kts IAS at sea level to about 85kts at 10,000ft.

Cruise in the test aircraft proved to be another relaxing experience for all on board; with 24/24 still showing, about 70 per cent power, 147 knots indicated showed up on the ASI at 4000ft, with fuel consumption calculated at a miserly 11gph (US).

With that combination, the aircraft could be flown about 670 nautical miles using standard 68gall (US) tanks.

Leaning at cruise height or above 5000ft is the usual EGl temperature control exercise.

Another conference with the other occupants on noise levels, ventilation in flight and other comfort factors again gave the 114 ten out of ten.

The cruciform tail assembly (which also houses a VHF nav antenna, ram air intake for cabin ventilation, and flashing beacon) does three main things – apart from its normal job; minimises prop-beat and thus cuts down vibration and other noise apparent in a conventionally-mounted horizontal stabiliser, promote es elevator “feel” and attitude controllability, and chops down pitch changes when cycling flaps or undercarriage.

From the front seat, it was patently obvious that the test aircraft’s obedience, response to power or manual inputs and general “feel” made it a natural IFR platform, either for training or operational work in charter, private owner or small corporate spheres.

Pouring on the coal is hardly necessary – or advisable in these fuel-conscious days in Australia – but if you want to get the 114 to max speed, one can look for about 166 knots at sea level, max gross, on a standard day.

At the operating height, it’s up to you, the EGT critical temperatures and the wind . . . Vne is carded at 175kts IAS. Other vital speeds include: Vno (max structural cruising) 137kts IAS; Vfe (max flaps extended) 150kts IAS; Vlo (max gear operating) 129kts IAS; Vie (max gear extended) 187kts IAS; Va (manoeuvring) 118kts IAS in Utility category.

Stalling a 114 is almost a non-event. A deliberate manoeuvre, considerable control surface buffet is experienced in both dirty and clean conditions. Clean, the test aircraft developed a sink rate with fore-and-aft pitching at about 59 knots – right on the book figure. There could be a tendency for a left-wing drop in both clean and landing configurations.

With wheels and flaps down, the test aircraft dropped through cleanly and most reluctantly at 54 knots indicated (one knot less than book) after complaining in loud and clear tones via airframe and controls.

In Utility Cat, the 114 is cleared for lazy eights, chandelles and steep turns – manoeuvres which most pilots keep to themselves unless demanded by masochistic passengers. For the record, entry speeds are Lazy eights (bank angle more than 60 degrees), 120 knots at 2800Ib. Chandelles (in excess of 60 degrees), 120kts at 2800Ib. Steep turns (in excess of 60 degrees), 120kts at 2800Ib.

Stalls, except whip stalls, obviously need slow entry speeds.

Rockwell’s manual says, incidentally, that maximum height loss during a wings-level stall recovery is 400ft. We made it far less, but did not allow the stall to fully develop – a situation we feel more suited to operational stall conditions.

Circuit and landing work is a relaxed form of mental and physical exercise in the 114, apart from neck work necessary in the Bankstown circuit where the AADR test team finds mini cross country exercises passing for circuits in a growing number.

With first-stage flap extension possible at 150 knots, keeping to circuit-joining speed is easy. Despite the test aircraft’s clean lines, slowing down is a non-problem.

Ninety knots were set up on downwind, with the undercarriage cycled well below Vlo of 129 indicated. Minimal pitch changes were apparent, thanks to Bethany’s cruciform tail.

Base negotiated at 80 knots, finals logged a steady 70 knots with full flap down in easy stages.

With just over 60 knots showing over the fence, the test aircraft was brought down in a flattish attitude and allowed to settle with a slight flare. A touch-and-go produced an instant response from both the engine and airframe.

The aircraft type is cleared for up to 19 knots crosswind – a surely conservative figure taking into account the rugged undercarriage and 11ft wheel track, plus known demonstration work showing off the sturdy undercard and rugged construction.

In summary, the Rockwell Commander 114 as tested is a truly delightful aircraft, a cut above the normal four-place tourer/corporate machine in both comfort and ease of operation in almost all weathers.

With assured long-life construction built into the type, a private owner would have a hard job to better the purchase of one of these beasts despite the initial outlay.

There are no apparent vices in the type. The only debatable point appears to be the range-payload equation, and sensible flight planning and logic can overcome that one.

Data Box:

Rockwell Commander 114. Single-engine four-place retractable, private/charter/small corporate type, low wing medium/long range.

Price of aircraft tested, $60,000, including extensive avionics panel. Aircraft evaluated supplied by Eastern Commander Air Enterprises Pty Ltd, 29 King Road, Hornsby NSW, phone (02) 476 1144. Price current at time of testing.

Specifications: max gross Normal 314016, Utility 280016. Standard empty 185816. Useful load Normal 1282Ib, Utility 94216. Baggage allowance 20016.

Wing loading 20. 7I6/sq ft. Power loading 12. 1I6/hp. Flight load factors (Limit), Normal, flaps up, + 3. 8G to -1. 52G. Utility, +4. 4G to -1. 76G.

Capacities: fuel (standard) usable, 68 US galls. Oil (max) 8 qts.

Engine: Lycoming Model 10-540-T4B5D, take-off power rating 260hp at 2700rpm; max continuous power rating, 260hp at 2700rpm.

Propeller: Hartzell 77in diameter two-blade constant speed.

Dimensions: wing span 32ft 9in. Length 25ft 0. Sin. Height (including beacon) 8ft Sin. Tread 10ft 11. 4in. Cabin height 49in. Cabin length 75in. Cabin width 47in. Baggage volume 22cu/ft. Baggage capacity 20016. No. of doors, two.

Performance (Manual & Rockwell sources): Max continuous at s/I, standard day, 166kts TAS; cruise 161TAS; stall (clean) 59kts. Stall (landing configuration) SSkts.

Cruising ranges: (68 galls, 2571lb), at 55 per cent power 731nm including reserve. At 75 per cent power, same fuel and weight, 643nm inc reserve.

Rate of climb, sea level, 1160fpm. Service ceiling 17,400ft.

Take-off performance: over 50 obstacle 1805ft.

Landing over 50ft obstacle, 1318ft.

limiting factors include: Vne 175kts. Vno 137kts. Vfe 1S0kts. Vlo 129kts. Vie 187kts. Va 118kts. Max cowl flaps open 129kts. Max side window open 129kts.