VOLUME I Multinational Maritime Tactical Instructions and Procedures

(2) The OTC (or screen commander, if delegated) normally allocates one or more helicopters to
each HCU.
(3) HCU passes to helicopters their sector boundaries and sector limits, or the bearings and distances
of their stations from a suitable reference point (e.g., QQ or ZZ)
(4) HCU directs the movements of the helicopters under positive control to ensure safety.
c. Procedure When Carrying Out Evasive Steering. When evasive steering is being carried
out, HCUs must coordinate helicopter movements with ship movements so as to avoid unacceptable gaps
in the screen.
(1) Very-Long-Leg or Long-Leg Zigzag Plan. When one of these plans is in force, helicopters
in the screen need only be informed of this fact and of the alterations of course at least one dip cycle
before they take place.
(2) Short-Leg Zigzag Plan. When this plan is in effect, helicopters in the screen may be taken
under positive control. Helicopters should not be employed along the short legs except in the direction
of the force movement.
d. Information to Helicopters. Helicopters must be kept informed of the situation by their
HCUs to enable them to perform their functions properly. Information, such as course and speed
alternations, evasive steering in use, adjustment of the screen, and contacts obtained by other units, are all
required by helicopters in the screen.
3335 PICKETS
a. Ordering. Picket stations are ordered either by true bearing and distance from screen center or
by the sector method.
NOT RELEASABLE
b. Maneuvering. The true bearings and ranges of picket stations do not change with alterations of
course by the main body or convoy. If new picket stations are desired, the OTC (or screen commander, if
delegated) should order them well in advance of the alteration of course.
c. NOT RELEASABLE
3336 TOWED ARRAY SHIPS IN THE SCREEN
The procedures for stationing surface ships equipped with towed array systems are similar to those
for other surface ships.
NOT RELEASABLE
a. and b. NOT RELEASABLE
MTP 1(D), Vol. I
3-48 CHANGE 2