wires, well and good; but if not, then
some of the internal framework probably requires replacement.

ADJUSTMENTS.--Verify the angles of incidence, dihedral, and stagger, and
the rigging position of the controlling surfaces, as often as possible.

UNDERCARRIAGE.--Constantly examine the alignment and fittings of the
undercarriage, and the condition of tyres and shock absorbers. The
latter, when made of rubber, wear quickest underneath. Inspect axles and
skids to see if there are any signs of them becoming bent. The wheels
should be taken off occasionally and greased.

LOCKING ARRANGEMENTS.--Constantly inspect the locking arrangements of
turnbuckles, bolts, etc. Pay particular attention to the control cable
connections, and to all moving parts in respect of the controls.

LUBRICATION.--Keep all moving parts, such as pulleys, control levers,
and hinges of controlling surfaces, well greased.

SPECIAL INSPECTION.--Apart from constantly examining the aeroplane with
reference to the above points I have made, I think that, in the case of
an aeroplane in constant use, it is an excellent thing to make a special
inspection of every part, say, once a week. This will take from two to
three hours according to the type of aeroplane. In order to carry it out
methodically, the rigger should have a list of every part down to the
smallest split-pin. He can then check the parts as he examines them,
and nothing will be passed over. This, I know from experience, greatly
increases the confidence of the pilot, and tends to produce good work
in the air.

WINDY WEATHER.--The aeroplane, when on the ground, should face the
wind; and it is advisable to lash the control lever fast, so that the
controlling surfaces may not be blown about and possibly damaged.

"VETTING" BY EYE.--This should be practised at every opportunity, and,
if persevered in, it is possible to become quite expert in diagnosing
by eye faults in flight efficiency, stability, and control.

The aeroplane should be standing upon level ground, or, better than
that, packed up into its "flying position."

Now stand in front of it and line up the leading edge with the main
spar, rear spar, and trailing edge. Their shadows can usually be seen
through the fabric. Allowance must, of course, be made for wash-in and
wash-out; otherwise, the parts I have specified should be parallel with
each other.

Now line up the centre part of the main-plane with the tail-plane. The
latter shoul