What to expect

What to expect when learning to fly on, or converting to, a Tiger Moth Type Aircraft

An introduction for ab-initio, or low-houred licence holders.

Quote:

"It is probably easier to start from scratch when learning to fly a Tiger Moth or similar type - rather than being weaned off post-war American varieties".

Here are some of the differences which need to be considered:

LEARN TO BE IN CONTROL, DESPITE

Tail down/3-point attitude.
Ground Manoeuvring.

No brakes.
Need to plan well ahead when taxying.

Open cockpit.
Not the most comfortable classroom.

Right swing with power.
Most modern aircraft swing left.

Few instruments + the compass.
Often no artificial horizon, direction indicator or vertical speed indicator.

3-point landing.
Lengthy dual may be needed to produce consistent safe touchdowns.

TAIL DOWN and NO BRAKES

On the ground, Tiger Moths sit tail down, so the pilot cannot see directly ahead. Taxying in a straight line is not good practice. If you have watched Tiger Moths manoeuvring you will, I hope, have seen them moving the nose from side to side for the pilot to have clear sight of the way in front.

Most Tiger Moths do not have mainwheel brakes. This means you must anticipate the taxy route more carefully than in a modern aircraft. Firstly, the Moth will not turn so well in a confined space: try to allow plenty of room or arrange for wing walkers. Secondly, slopes are very significant, particularly downhill. If control is in doubt, switch off the engine.

OPEN COCKPIT

If you want to fly an open cockpit Moth, then you will be working "outside". It can be quite a harsh environment depending on the season and the location in the world.

Suitable clothing can help a lot.

The military surplus suppliers usually have stocks of flying overalls and gloves. Several specialist companies make leather and fleece Irvin-type jackets and fleece-lined boots. ‘Long Johns’ or skiing thermals are useful. The type of protective kit required will depend on where you are intending to fly and whether you will be operating throughout all the seasons of the year.

For communication the purist would only have a leather helmet and Gosport speaking tubes. However, the majority of Moths are now fitted with radios and intercom. Most Moth pilots have ex-military leather or cloth helmets fitted with masks and electrics or sometimes ex-military ‘bone-domes’. Reception is often not 'hi-fi'. If the mask microphone is left "on" heavy breathing and wind noise can be distracting. With a helmet, goggles are necessary. The traditional Mk VIIIs are available. Lightweight motorbike or ski goggles are arguably more comfortable. Specialist opticians are able to fit prescription lenses in the Mk VIIIs.

One of a number of different types of safety harness may be fitted and when adjusted it needs to be tight but comfortable without restricting vital movement.

The Tiger Moth seat was designed to take a military parachute but in civilian use the seat is usually filled with a wooden former tailored for the job, on top of which cushions can be fitted and adjusted as required. It is important that the pilot’s line of sight is assured and that he/she can easily reach and operate all hand and foot controls.

RIGHT SWING WITH POWER

Unlike most modern engines, the Gipsy Major engine rotates anti-clockwise as seen from the pilot's seat.

The four factors of:

1. Asymmetric blade effect (different angle of attack of the propeller blades whilst tail down)

2. Gyroscopic effect (as tail rises force precessed 90deg anti-clockwise)

3. Slipstream

and

4. Torque (right wheel pressed harder into the ground)

all encourage the aircraft to swing to the right when power is applied. If already a pilot with hours on other types, it might take a little while to get used to this and to put in appropriate left rudder to keep straight.

Most modern types swing to the left.

FEW INSTRUMENTS (+ THE COMPASS)

The Tiger Moth probably only has Air Speed Indicator, Altimeter, Turn and Slip and P-Type compass; often no Artificial Horizon, Direction Indicator or Vertical Speed Indicator.

Those latter instruments have unwittingly helped with straight and level flight in modern aeroplanes. In a Tiger Moth you rely rather more on external cues, which may also improve look-out. The Slip Indicator takes on a much greater significance (encouraged by your instructor to use your feet.) The compass is accurate but again requires practice in its use.

3 POINT LANDING

The tail-skid Moths are satisfying to land, when done well.

Tricycle undercarriage aeroplanes have their C of G between the wheels. On touchdown, with any residual rate of descent the nose will pitch down. The angle of attack reduces so lift will be less, and you stay on the ground.

With a tailwheel, if touchdown occurs on the mainwheels with significant rate of descent, the angle of attack will increase, the aircraft will bounce, and the extra lift will get you airborne again, possibly at low speed.

HANDLING SUMMARY

By phase of flight. These areas are important.

ON THE GROUND

The poor view. Do swing the nose to ensure the way ahead is clear. Plan your route and anticipate problems, particularly in confined areas and on slopes. Be careful.

TAKE OFF RUN

Directional aspect: anticipate the swing to the right. The good news is that performance is good and the run is short, unless the aircraft is fitted with a particularly coarse pitch propeller.

IN-FLIGHT

Communication between cockpits relies on the intercom. Unlike when riding a tandem bicycle, there is little scope for body language. A hunched instructor in the front seat is probably more to do with avoiding the draught than your flying. The long established 'you have control' and 'I have control' takes on greater significance.

For general handling, the Slip needle is, for most people, something of a shock. Keeping it central will stop the blast of air from the side, and means you are flying efficiently.

If you drop something in the cockpit you will probably not see it again until the next slow roll, and then only fleetingly. You can tie down pencils and it is good practice to carry a spare map.

LANDING

It takes a little time to learn to land a Moth.

One of the points to understand is that the landing itself takes time. A Moth is not just 'put on the ground'.

The flare is started about 'double decker bus' height.

The hold-off is that period of time as the aeroplane is allowed to decelerate, whilst maintaining substantially straight and level flight. It is really an example of the 'Straight and Level Part 2 Air Exercise', where you learn to fly level and change speed. As you slow-up you progressively raise the nose to keep level flight.

Be prepared for the load on the control column to increase due to the spring of the tail plane trimming system.

Towards the end of the hold-off, the speed will be approaching the stall and the attitude will have increased.

Touchdown occurs at low speed. The drag of the wheels and skid slow you quickly to below flying speed.

Throughout all this the instructor will probably be exhorting you to keep pulling the stick back. This will produce the desired result as long as it is done at the correct rate.

Once down do not relax too soon. Rudder, perhaps in increasing amounts, may be needed to maintain direction. With the C of G aft of the wheels, a ground loop may occur if attention is allowed to wander.

CONCLUSION

I am prepared to suggest that flying these old aeroplanes is wonderful fun.

Learning the techniques may be difficult at times. Perhaps the great C.P.I. above meant it to be like that.

For some, flight in an open-cockpit Moth is a heady cocktail of Cecil Lewis, W.E. Johns, Gillespie Magee and Saint Exupéry.

P.B.