barricade webbing assembly, the barricade power
package, and the barricade stanchion assemblies in
this chapter.
ARRESTING ENGINE
The Mk 7 arresting engine is a hydropneumatic
system composed basically of the engine structure,
a cylinder and ram assembly, the crosshead and
fixed sheaves,
a control valve system, the
accumulator system, auxiliary air flasks, and a
sheave and cable arrangement.
Improvements are continuously being made to
increase the capabilities of carrier-based aircraft. As
the capabilities of the aircraft are increased, the
weight and speed also increase.
Therefore, the
equipment used to recover the aircraft aboard
carriers must also be improved to keep pace with
aircraft advancement.
Such improvements have
brought about the recovery equipment installed on
our carriers in the fleet today—the Mk 7 Mod 2
and Mod 3.
Table 3-1 lists the leading particulars of the
Mk 7 Mod 2 and Mod 3 recovery equipment.
Table 3-1.—Leading Particulars of Mk 7 Recovery Equipment
Mod 2
Mod 3
MAXIMUM ENERGY ABSORPTION:
Service stroke
38,000,000 ft-lb
47,500,000 ft-lb
ENGINE DRIVE SYSTEM CABLES:
Breaking strength/diameter
Deck pendant (6 x 30 flattened strand)
188,000 lb/1 3/8 in.
188,000 lb/1 3/8 in.
Purchase cable (6 x 25 round strand)
195,000 lb/1 7/16 in.
195,000 lb/1 7/1 6 in.
Reeving ratio
18 to 1
18 to 1
ARRESTING ENGINE:
Length
50 ft
50 ft
Weight
37 tons
43 tons
Engine fluid
Ethylene glycol
Ethylene glycol
Engine fluid capacity (without cooler)
320 gal
380 gal
Engine fluid capacity (with cooler)
500 gal
560 gal
Ram diameter
18.495 in.
20.000 in.
Effective ram area
268.8 sq in.
314.16 sq in.
Length of maxim urn stroke
186.00 in.
192 in.
Length of service stroke
171.00 in.
183 in.
Crosshead battery position
1 to 7 in.
1 to 6 in.
(distance from stop)
Accumulator operating medium
Ethylene glycol/air
Ethylene glycol/air
Maximum pressure
650 psi
650 psi
Initial working pressure
400 psi
400 psi
Type of coolant
Seawater
Seawater
Length of runout
310ft
340 ft
3-5
