NFC Learning

Slotted aloha. A random access strategy whereby multiple users access the same communications channel independently, but
each communication must be confined to a fixed time slot. The same timing slot structure is known to all users, but there
is no other coordination between the users.

Slush. Water-saturated snow which with a heel-and-toe slap- down motion against the ground will be displaced with a splatter;
specific gravity: 0.5 up to 0.8.
Note.C Combinations of ice, snow and/or standing water may, especially when rain, rain and snow, or snow is falling,
produce substances with specific gravities in excess of 0.8. These substances, due to their high water/ice content, will have a
transparent rather than a cloudy appearance and, at the higher specific gravities, will be readily distinguishable from slush.

Smoke. The carbonaceous materials in exhaust emissions which obscure the transmission of light.

Smoke Number. The dimensionless term quantifying smoke emissions (see 3 of ICAO Annex 16, Appendix 2).

Snow (on the ground).
a) Dry snow. Snow which can be blown if loose or, if compacted by hand, will fall apart again upon release; specific
gravity: up to but not including 0.35.

b) Wet snow. Snow which, if compacted by hand, will stick together and tend to or form a snowball; specific gravity:
0.35 up to but not including 0.5.

c) Compacted snow. Snow which has been compressed into a solid mass that resists further compression and will hold
together or break up into lumps if picked up; specific gravity: 0.5 and over.

SSALF - Simplified Short Approach Lighting System with Sequenced Flashing Lights

SSALR - Simplified Short Approach Lighting System with Runway Alignment Indicator Lights

SSALS - Simplified Short Approach Lighting System

SSR response. The visual indication, in non-symbolic form,
on a radar display, of a response from an SSR transponder
in reply to an interrogation.

Standard isobaric surface. An isobaric surface used on a worldwide basis for representing and analysing the conditions in
the atmosphere.

State of Design. The State having jurisdiction over the organization responsible for the type design.