Nanchang Airtest

The Nanchang CJ-6A is a tandem two seat basic military trainer developed in China for the Peoples Liberation Army Air Force (PLAAF) from the ubiquitous Russian Yak-18 series. The Chinese licence built the Yak 18 as the Nanchang CJ-5. The follow on CJ-6 is an all metal cantilever monoplane developed from the Yak-18A and continues in service with the PLAAF, the Bangladeshi Air Force, the Zambian Air Force, and it is understood, the air arms of North Korea and Albania.

The CJ-6 was developed in the late 1950’s and early 1960’s after the break in Sino Soviet relations. The Chinese required a more advanced primary trainer than the Yak-18 and so they developed their own more or less in parallel with the totally indigenous JJ-1 intermediate jet trainer. When the PLAAF adopted a training program which took pilots directly from the CJ-6 to the Shenjang JJ-5, the Chinese version of the MiG-15UTI, the JJ-1 development was discontinued. The CJ-6 powered by either the Russian AL14 or the Chinese Housai 6 engine of 260hp was superseded in 1965 by the CJ-6A with the HS6A engine of 285hp. The only armed version of the aircraft were 10 retrofitted CJ-6A aircraft designated as CJ6-B’s. As an introductory trainer for jet fighter type aircraft, the CJ-6 at 1,400kgs MTOW (max takeoff weight) and 285hp is a very different approach to the American T-28 Trojan at 4,535kgs MTOW and 1,425hp.

The aircraft is a low wing monoplane fitted with a retractable tricycle undercarriage and low pressure tyres for grass strip operations. The engine is a Housai 6 supercharged 9 cylinder radial, which is pneumatically started. The propeller is a constant speed type with two metal blades. The one-stage flap and landing gear are also pneumatically operated as are the brakes.

Preflighting the aircraft, it is readily apparent that it is a solidly built machine, obviously designed to take the punishment that can be handed out in the training role. As was pointed out by Brian Candler who took me for my familiarisation ride, a screwdriver is an essential tool when conducting the preflight as there are a great number of panels to be removed in the process. It was interesting to observe the difference in philosophy between east and west in such matters as removing a panel to inspect the aileron bell cranks, something I had never come across before.

On entering the cockpit I was impressed with the relatively roominess and ease of reach of all switches and controls of which there are quite a few. Again there was an immediate impression that there was a philosophy of giving the pilot greater control over functions not normally provided in western aircraft . By way of example there is a switch to provide a reading of oil temperature at the outlet from the tank or from the engine return. The latter is a useful control observing that the oil tank holds 17 litres and hence there is a need to know that all the oil has been heated through prior to run-up.

No parking brake is provided which requires care that the aircraft doesn’t roll forward whilst warming up at 1,000rpm.

Similarly there is no rudder trim and although rudder forces are not heavy, one is aware of the load being carried by the left leg. A nice touch is a light on the instrument panel to indicate neutral elevator trim; the latter control is sensibly placed to the left of the upper instrument panel. Another useful indicator is a striped pole which pops up in front of the windscreen when the undercarriage is lowered; this is in addition to an indicator which shows three greens when the gear is down and three reds when it is retracted.

Flap down indication is provided by another pole which emerges from the wing surface, which I must admit I found hard to see. The flight instruments are easy to read and have been placarded in English at CAA direction, a sensible move. The rear cockpit remains however, in its original state.

Fuel is carried in two tanks, one in each wing and fuel transfer is effected through tank pressurisation; there are evidently no problems with the system attempting to feed from an empty tank. A total of 150 litres is usable which provides an endurance of 2. 5 hours at aTAS of 135 knots.

As all the services including engine start are pneumatic, it is essential to conserve air pressure to achieve a start, and for taxying. As part of the drill when taxying, the air pressure recuperator is isolated to provide a reserve in the event of a system failure. I was surprised to find that the system had held its pressure since the aircraft had last been flown which was over a week previously and a start was achieved without having to resort to external air bottles. However, I must admit I was a little slow catching the motor on the primer but achieved it in the end.

There is nothing quite like the sound and sight of a radial rumbling away at the front end, my immediate impression was of a Sea Fury in miniature!

Brian was at pains to point out that the brakes were hand operated by lever with differential braking through the rudder bar and that most people had difficulty getting to the holding point. Fortunately I cut my teeth in the Firefly many years ago with precisely that system, and hence it wasn’t a problem for me.

There was even sufficient control through coarse rudder for wider turns if the revs were kept up as was the case with the Firefly. Two other aspects of the aircraft that endeared it to me were firstly that the engine rotated the “correct way” (British!), and secondly, joy of joys, a left hand throttle/right hand stick set up.

On safely arriving at the holding point, I was surprised to note that there was no perceptible drop in revs on either magneto on engine run up.

Takeoff was fairly straight forward with a touch of left rudder to counteract torque. Care needs to be exercised however that the nose is not raised too high prior to lift off as the aircraft will unstick at too low a speed. Raising the undercarriage requires a slide lock to be pushed to the left and the system to be primed by first pushing the lever in and moving it from the neutral position to down and then to up. This primes the system and prevents shock loads on the gear and airframe as I was to discover when I failed to follow the correct procedure. A similar routine needs to be followed on lowering the undercarriage.

Climb out is normally made at 100 knots with 2,150rpm and 28in boost; best climb speed is 91kts with 2,250rpm and 32in which gives over 1,200fpm.

We soon reached our cleared height of 6,000ft and on establishing ourselves in the training area I tried afew steep turns. These were made easy by the relatively long nose (shades of the Sea Fury!) and it was a simple matter to hold height through 360 reversing turns. I didn’t pull it to the limit in deference to Brian in the back and the CAA operating clearance, but we were sustaining respectable ‘g’ with no sign of control snatch or high speed stall. The power-off clean stall was straight forward at about 60kts with no unpredictable tendencies. The same was true of the dirty stall which surprisingly occurred at the same speed. This is because the flap, which has only one setting, only serves to alter the attitude of the aircraft, ie; provide a lower nose position in the approach configuration. (I’m still trying to work out the aerodynamics there!)

Brian then got me to stall the aircraft again with everything down and to recover with power alone, without altering the attitude of the aircraft. It was a fairly convincing demonstration of the need to watch the attitude and sink rate on the approach, as power alone took a long time to effect a recovery.

On return to the circuit we had the inevitable bomber pilot practising his skills in a Cessna which did however provide an opportunity to observe the reduction in view over the nose on a long straightaway as we trailed along behind him.

As a result of this, I had a powerful urge to fly the type of circuit we used to fly when ashore in the old straight-deck carrier days, 400ft and a constant curve with plenty of power. I managed to fly one tightish circuit and it felt much more comfortable as the problem of trying to see over the nose as you raised it to wash off speed was overcome. It occurred to me that a night flightless with a left crosswind would be interesting!

Landings were fairly straight forward but a nose high attitude is necessary to keep the nose wheel off. On touch and goes, a tad of power was added and the flaps raised before lifting off which ensured a clean unstick.

On the final landing I found that there was plenty of elevator control to sustain useful aerodynamic braking, aided by the fore and aft balance of the aircraft on the main wheels.

When shutting down, there was one slightly jarring note and that this was done by switching off the ignition; something we were told never to do once we had progressed beyond the Tiger Moth phase. I suppose opening the throttle fully as the ignition is cut makes it slightly less of a sin.

My impressions of the aircraft? I liked it; it has solid feel, handles well and is a pleasure to fly. It would make an ideal warbird for the less experienced and would be an excellent transition aircraft to the faster machines. It certainly has charisma if only because of its origins which certainly make it different!

If you are thinking of getting into the warbird scene Graeme and Brian would be well worth talking to. Having successfully imported three Nanchang CJ-6As into Australia they have also arranged the export of a further six into the USA. They believe more CJ-6 and the earlier CJ-5 (Yak 18) will soon be available. for something completely different or for the more ambitious, they are currently working on obtaining examples of the Harbin Y5 (An-2). The super ambitious might want to consider the Shenyang JJ-5 (MiG-15 UT/). Through their contacts, mentioned earlier, they are also able to provide technical support for the aircraft they import. They can be contacted on (06) 280 4544 BH or fax (06) 280 4516