Britax Safe'n'Sound Instructions For Installation & Use page 40

HOW TO INSTALL IN AN AIRCRAFT
C. Place handle in "non-rocking" position,
that is, fully backwards. Fully lengthen lap
belt. Thread the lap belt into
REARWARD-FACING BELT
PATH
lap belt path (green marker) as
shown, ensuring that lap part is below the
hook as shown, on each side. Engage lap
belt buckle and tongue.
D. Push down on the Baby Capsule and
remove all slack from the lap belt. Pull belt
strap to tighten, ensure a firm fit of the Baby
Capsule to the seat.
Do not use this restraint with aircraft seatbelt
that contain airbags unless they can be
disabled.
Do not use with a seatbelt extender that
causes the buckle to enter the hook area of
the aircraft belt path.
40
Instructions for Installation & Use
AIRCRAFT
Ensure lap
belt is under
the hook on
each side
C
D
Remove slack