CHAPTER 3
MK 7 AIRCRAFT RECOVERY
EQUIPMENT
Present-day aircraft normally require the use of
runways that are 5,000 to 8,000 feet long in order to
land ashore. On an aircraft carrier, these same aircraft
are stopped within 350 feet after contacting the deck.
This feat is accomplished through the use of aircraft
recovery equipment, including an emergency barricade
that brings a landing aircraft to a controlled stop by
absorbing and dispelling the energy developed by the
landing aircraft. This recovery equipment is commonly
called arresting gear.
The sole purpose of an aircraft carrier is to provide
a means of launching a strike against an enemy
anywhere in the world. After the aircraft complete their
mission, the carrier must provide a means of safely
recovering them. The Mk 7 arresting gear provides this
means.
AIRCRAFT RECOVERY
LEARNING OBJECTIVE: Describe aircraft
arrestments aboard aircraft carriers. Describe
prerecovery preparations. Describe normal
aircraft
recovery
operations.
Describe
emergency aircraft recovery operations.
Aircraft arrestments aboard carriers are classified
as either a normal arrestment or an emergency
arrestment. Simply stated, arrestment is accomplished
in the following manner: the arresting hook of the
incoming aircraft engages a wire rope cable, called a
deck pendant, that spans the flight deck in the landing
area. The force of the forward motion of the aircraft is
transferred to purchase cables that are reeved around a
movable crosshead of sheaves and a fixed sheave
assembly of the arresting engine (see fig. 3-1). The
movable crosshead is moved toward the fixed sheave
assembly as the aircraft pulls the purchase cables off
the arresting engine, forcing a ram into the cylinder
holding pressurized hydraulic fluid (ethylene glycol).
This fluid is forced out of the cylinder through a control
valve that meters the flow to an accumulator until the
aircraft is brought to a smooth, controlled arrested
landing (see fig. 3-2).
After arrestment, the aircraft's arresting hook is
disengaged from the deck pendant. A retract valve is
then opened, allowing fluid to be forced from the
accumulator back into the engine cylinder, forcing the
ram out. As the ram moves out of the cylinder, the
crosshead is forced away from the fixed sheave
assembly, pulling the purchase cables back onto the
engine until the crosshead is returned to its BATTERY
position and the crossdeck pendant is in its normal
position on the flight deck.
PRERECOVERY PREPARATIONS
Prior to recovery of aircraft, all recovery equipment
and landing area must be made ready and all personnel
properly positioned. The following is a general listing
of the events that must be accomplished prior to the
recovery of aircraft:
All operational retractable sheaves raised to the
full up position
All aft deckedge antennas positioned, as
required
Ready barricade, including deck ramps, in a
ready status with a clear route to the landing area
and a tractor with driver standing by
All launching accessories clear of the landing
area
Appropriate catapult shuttle(s) (as applicable)
are aft with the grab latch disengaged and the
shuttle spreader cover installed
The catapult centerdeck hatch and any other
hatches in the waist catapult area closed and
dogged down
Jet Blast Deflectors (JBDs) completely lowered
and hydraulics secured
Waist catapult safety light in the down position,
if applicable
Catapult #3 track slot buttons installed
Waist catapult Integrated Catapult Control
Station (ICCS) fully lowered, if applicable
3-1
