What engines are on the metro?
Garrett turboprop
- -10 engines 840hp
227AC. -11 1000hp dry. 1100hp wet
227BC
227DC. -12 engines. 1100hp takeoff
1000hp max continuous
What is max fuel?
4342 lbs
648 gallons of Jet
What is the service ceiling differences between metros?
- FL250
227ac,bc. FL310
227DC. FL250
What are the wingspan differences?
- 47’
227’s. 57’
What is forward baggage weight capacity?
Placard on door will dictate the weight capacity.
Normally 800lbs -minus the installed equipment aft of bulkhead
What is CAWI and how much is used on each of the planes?
CAWI - continuous alcohol/water injection
Used to add temporary performance by increasing compression ratio of the engines when injected to help assist on takeoff during certain airport of aircraft conditions.
Metro 23 227DC. 16 gal capacity with 14 usable
Located in 2 inboard tanks
Other birds 16 gal capacity and usable same
Tank located in bladder inside nose
What is the limitation on how long CAWI can be used?
5’ takeoff limitation
Burns 2.4 gallons per minute per engine
What all is located in the tail section?
- Avionics Rack
- oxygen
- pneumatic relay
- outflow valve
Explain the main cabin door, operation and it’s limitations?
Main cabin doors is an integral part of the airframe.
- Consists of 7 bayonets and 2 alignment pins
(Rod pushes out and pushes latches) - gas struts (compressed air)
(Operator must support door while opening)
(Older birds than 650 SN#, 7 click-clacks and 2 pins)
- Never tow aircraft with door open as it can permanently damage airframe as well as door
- make sure bayonets are retracted before shutting door or damage
What is the pressure diaphragm lock?
A pressure actuated diaphragm lock that uses:
- an inflatable rubber seal below
Moves mechanically to hold door locked when pressurized in flight
Cargo door consists of:
- 8 click-clacks
- 2 alignment pins
How many emergency exits? Explain
2 on either side of cabin
Main cabin door is considered one of the 2 on left side
Cargo door test light switch… Explain how it works..
Unlock cargo door then perform test.
Rocket switch-
- lamp test
- switch tests micro switches
Emerg exit signs
Sign lights up with Hazmat Tritium material
2 signs on left and 2 on right
Windshields
Explain
5 windows upfront
- 2 double pane electric heat
- 3 stretched acrylic
Explain electrical battery system
2 AC batteries
(located onboard engine pylons)
24 v lead acid (must have at least 24v to start)
2 starter generators (DC 28v)
Started generates power when up to speed
2 static inverters convert DC to AC 115 26V
GPU plug
(Located on Wing root Metro 23, #1 engine nacelle others)
Explain 9 electrical essentials
IFPIG
Instrument pilots DC
Fuel Crossflow valve
Pressurization Dump
Ice Equipment
- surface deice boots
- left/right Engine Intake Heat
- L windshield Heat
Gear
- landing gear control
- landing position indicatorSignificance:
9 essentials are on pilot side console and in the event of issue can be moved over to right side
Fuel system
Fuel Jet A stored in integral wing tanks
- A crossflow valve connects each wing tank (Elect power by essential bus)
- 2 Aux Boost pumps
(powered by opposite essential bus)
Magnasticks - backup fuel quantity indicator system
From 200-1000 lbs
Prop
- Controlled with counter-weight spring force
- Oil feathers blades
High and Low positions not condition levers
Engine gauges
- EGT max 650 normal operations
- Torque. 0-100%
- RPM
- Fuel Flow
- Oil Temp
Fire suppression system
Metro 2 - detection only
All other Metros- Detection and Suppression Extinguishers
Pneumatic system
Runs off of engines
Operates: AC
pressurization system
18/21 pneumatic system
-uses regulated and un-regulated bleed air and vacuum.
Either engine is sufficient to meet all requirements, but both are normally used.
Regulated bleed air is used for:
- pressurization
- air-conditioning
- deice boot inflation
- window defogging
- hydraulic reservoir pressure
- door seal inflation
- vacuum generation.
Unregulated bleed air is used for engine and nacelle inlet anti-icing.
De-Ice System
Boots
Wing and Horizontal Stab
18psi to open
Closed by vacuum
Engine Inlets - Bleed Air
Props- Electric heated strips
Pressurization system
7 psi Normal Pressure
Holds sea level pressure to 16,800’
2 safety relief valves - limit cabin pressure to 7.25 if pressurization controller fail
outflow valve controlled by PIC - back of plane bulkhead
At 7.31 backup outflow valve opens
Gauges
Press controller - asks system what to do
Cabin press selector-
Cabin rate - vsi
