Operation Manual

27
VT 4.0 OPERATING MANUAL
© 2002 Design, 2011 Doc. No. 12-5213-r02 (9/6/11)
DECOMPRESSION
Decompression mode activates when theoretical No Decompression time and depth limits are exceeded.
Upon entry into Deco, the Audible will sound during which the alarm LED and full TLBG will flash. Two Up Arrows will also flash
(Fig. 51), until within 10 FT (3 M) of and below the required Stop Depth (the Stop Zone).
• S (< 2 sec) to silence the Audible.
> Once within 10 FT (3 M) of and below the required Stop Depth (the Stop Zone), the full Stop icon (smaller Up and Down
Arrows with Stop Bar) will be displayed solid.
Managing Deco Stops
To fulfill your decompression obligation, you should make a safe controlled Ascent to a depth slightly deeper than, or equal to,
the required Stop Depth indicated and decompress for the Stop Time indicated.
The amount of decompression credit time that you receive is dependent on Depth, with slightly less credit given the deeper you
are below the Stop Depth indicated.
You should stay slightly deeper than the required Stop Depth indicated until the next shallower Stop Depth appears. Then, you
can slowly ascend to, but not shallower than that indicated Stop Depth.
DECO STOP MAIN, information includes (Fig. 52) -
> Current Depth with FT (or M) icon.
> Nx, (PZ+), CF icons - if they apply.
> Graphic DECO STOP with Stop icon (arrows and bar).
> Stop Depth with graphic FT (or M) and Stop Time (up to 599 min) with graphic MIN.
> Pressure with PSI (or BAR) and Link icons.
> Graphic GAS1 (or 2, 3, 4), one in use.
> ATR (up to 199 min) with icons.
> TLBG, VARI - if they apply.
• A (< 2 sec) to access ALTs.
• M (2 sec) to access Gas/TMT Switching*.
• S (< 2 sec) to activate Backlight or acknowledge alarms.
• S (2 sec) to access Compass*.
*These items can only be accessed while viewing the Main.
Deco Stop Alt 1, information includes (Fig. 53) -
> Graphic ALt 1.
> Time of Day (hr:min) with graphic A (or P) if 12 Hour.
> Temperature with ° icon and graphic F (or C).
• A (< 2 sec) to access ALT 2.
• Revert to Main in 5 sec, if A is not pressed.
Deco Stop Alt 2, information includes (Fig. 54) -
> Graphic ALt 2.
> Max Depth with graphic FT (or M) MAX.
> EDT (min) with graphic.
> Total Ascent Time (up to 599 min) with TAT and min icons.
• A (< 2 sec) to access ALT 3 if Nx, or revert to Main if Air.
• Revert to Main in 5 sec, if A is not pressed.
Deco Stop Alt 3, information includes (Fig. 55) -
> Graphic ALt 3 with Nx icon.
> %O2 accumulated with graphic O2 SAT.
> PO2 value (x.xx ATA) with icon.
> Graphic GAS 1 (or 2, 3, 4), one in use.
> FO2 with icon, value set for Gas in use.
• 5 sec or A (< 2 sec), revert to Main.
Fig. 51 - DECO ENTRY
Fig. 52 - DECO STOP MAIN
Fig. 53 - DECO STOP ALT 1
Fig. 55 - DECO STOP ALT 3
Fig. 54 - DECO STOP ALT 2