and a control valve. All the components are mounted
reason, personnel must avoid the exhaust area
on a removable panel, except the highly sensitive
and make sure that the exhaust is not directed
pressure gauge stowed in the case cover. Refer back to
onto anything that the heat or the velocity of
figures 12-16 and 12-19 for illustrations of fuel, oil,
these gases could damage. A tragic fire in the
and pneumatic components. The pressure lines are
carrier U.S.S. Forrestal was started by the
locally fabricated and interconnected between the
exhaust from one of these units. Always be
engine systems and the analyzer gauges. The pressure
certain that the exhaust is no closer than the
gauge stowed in the analyzer cover is used to check
prescribed distance from any object.
fuel cracking pressures. Refer to the applicable engine
Keep clear of the plane-of-rotation of the
technical manual for the procedures necessary to
compressor and turbine assemblies. It is possible
connect the fuel, oil, and pneumatic components of the
for a turbine blade to shear off and be thrown out
analyzer into the engine systems.
of the turbine. At the speeds that the turbine
turns, the blades become like rifle bullets.
CAUTION
Usually these areas are marked clearly with red
painted stripes.
Apply foreign object damage (FOD) practices
when working with gas turbines. All personnel
Always wear sound attenuators when working
are aware of the destruction caused to an aircraft
on or near operating gas turbines. The noise level
jet engine when a foreign object is ingested; a gas
from a gas turbine is very high and can cause loss
turbine compressor can also be destroyed, or
of hearing. The use of the sound attenuators
seriously damaged, if the inlet area is not kept
cannot be over stressed. Remember, a loss of
clear of foreign objects. Never carry loose
hearing due to the high-frequency component of
articles, such as pencils or oil-wiping cloths, in
the noise generated by this equipment can and
your pockets when working near operating units.
often does cause permanent damage to the
Always inspect the entire area around the
auditory system.
equipment before starting the unit to make sure
Operational limits for specific engines are
no loose gear or debris can be pulled into the
compressor.
spelled out in the applicable technical manuals.
If the operational limits for a specific engine are
exceeded or if seizing, unusual noise, smoke,
fuel or oil leakage, or other obvious
SAFETY
malfunctions are observed, personnel and
equipment safety require that the engine be
In the operation of any gas turbine compressor
SECURED IMMEDIATELY. The cause of
unit, you must first become completely familiar with
trouble must be determined and corrected before
the proper operating procedures. You should not
restarting.
attempt to operate this equipment until you have an
operational checkout by a qualified and authorized
Prior to an engine operating test run, ensure that
operator and you have a valid SE operator's license.
the engine is securely mounted in its enclosure or
The actual operation of gas turbine compressors is
a test stand that provides adequate
s i m p l e ; h ow eve r, t h ey a r e p ow e r f u l p i e c e s o f
instrumentation to indicate operating
equipment and must be treated accordingly. The
conditions.
following safety precautions must be strictly enforced
Allow only authorized personnel in the vicinity
to prevent possible personnel injury or equipment
of the test area during engine operation.
destruction.
Keep clear of the compressor inlet. Although the
Q12-21. Which of the following terms is used to
turbine engine of the unit is small, as compared
describe the unauthorized removal and
to the engine in an aircraft, it is very dangerous
replacement of parts as a method of
and sucks in great quantities of air.
troubleshooting?
Keep clear of the exhaust area of gas turbines.
1.
Pin pointing
The exhaust gas from this equipment is exactly
2.
Winging it
like that of the engine in an aircraft--HOT--and
3.
Shotgunning
it exits from the unit at a terrific velocity. For this
4.
Short cutting
12-38
