4.3 Intro/Ops of E-28s Flashcards
What are the components of the arrester engine?
- Tape drum & capstan assembly
- Retrieve drive sprocket and bearing assembly
- Vaned rotor mounted on a common shaft assembled in a vaned housing.
What is the mission of the E-28 gear?
It is emergency arresting gear designed as a land-based, emergency standby gear for all tail hook equipped aircraft.
It’s installed on the runway for the purpose of safely arresting an aircraft during an aborted take-off or an emergency landing.
What are the components of the retrieve assembly?
- electrical starting system (12v for the 65 Hp engine)
- torque converter with front disconnect clutch
- speed reducer with duo-cam clutch
- control panel
What is the function of the tape drum, shaft, & rotor?
To function as one unit during an arrestment–the tape drum drives the rotor, whose motion is resisted by turbulent fluid in the housing, decelerating the tape drum.
Where is the tub housing installed?
Underground with fixed stators on the bottom and under the cover
Retrieve drive sprocket assembly is what & does what?
Bearing mounted, on the shaft above the tape drum
Retrieve system is automatically disengaged from the tape drum through the action of cam release post acting against the automatic release mechanism
What is the release mechanism spring loaded to?
6,000-6,500 lbs
How is the sprocket driven?
Chain driven by a gasoline engine
How is the retrieve system operated?
Manually engaged to the tape drum through contact of the armed spring loaded cam & cam release post
The tape drum and rotor run free of the sprocket assembly when the release mechanism is tripped
What is the function of the retrieve system assembly components?
- Rewinds the tape and pre-tensions the pendant after each arrestment
- control panel monitors all operations of the retrieve system
What is e purpose of the runway edge & deflector sheaves?
To serve as a guide for the nylon tape (purchase tape)
Deck pendant
1 1/4 inch diameter non-rotating wire rope
Arresting hook engages the deck pendant causing tape to pay out and activate the arrester engine
Tape connector
Connects the nylon tape to the deck pendant
What is the function of the cooling system?
When the retrieve engine is running cool fluid from the tank is pumped into system causing heated fluid to be forced back to the cooling tank
Large exposed surface of the tank serves as a heat exchanger, dissipating excess heat to surrounding air.
Located near arresting engine
Tape pressure roller
- Ensures even, tight wrapping of tape during retreive
- prevents over spin during arrestment
- tensioned by two springs extended by a hand winch
Base cover
Protects tape from exposed ends of arrester engine or runway edge sheave hold down bolts
Mounting base plate
Arrester engine assembly, deflector sheave assembly, pressure roller assembly and retrieve assembly are all bolted to a common base-plate
What is another name for the Johnson Ball?
Arrest sign
What is anger name for the arrest sign
Johnson Ball
What is the purpose for the arrest sign (Johnson ball)?
- Indicates to approaching aircraft the location of the arresting gear
- It’s a bi-directional illuminated sign that’s inline with the deck pendant behind the cooling system
- universal marker (FAA approved)
What does CDP stand for
Cross deck pendant
What does PTWS stand for
Pre-tension warning system
What is the PTWS used for
It provides continuous indication on the state of pretension on the deck pendant across the runway
What happens if the pretension is lost on the deck pendant
The PTWS strobe light flashes (it faces the tower)
