21 JANUARY 2003
Figure 4.1. Modified Panero, Type I Hydrant System.
4.3. Modified Panero System Operation. When fuel is required at a hydrant outlet, the operator
places a magnet on the refueling magnetic control assembly KISS switch). This energizes the
preselected system refuel pump and the solenoid on the 302AF valve. As fuel is pumped through the
system it flows through several components. Use Figure 4.1 to follow the fuel flow. Fuel is stored in
underground operating storage tanks. A pumphouse sits directly over the underground tanks. The
pumphouse contains pumps, F/Ss, piping, valves and other components. The pumps draw the fuel from
the tank and force it through the F/S at a rate of 1135 to 2271 liters per minute (300 to 600 gallons per
minute). The fuel flows into the main refueling manifold that connects to several lines called laterals.
Along the laterals, the line passes through a filter meter pit. In this pit, the fuel is filtered and metered
before it passes through a 302AF refuel/defuel control valve. The control valve reduces the fuel
pressure before fuel is delivered to the hydrant outlet where a hose is used to connect the system piping
to the aircraft. The 302AF valve also controls system defuels. When the magnet is removed from the
KISS switch, the pump and the 302AF solenoid both de-energize. The 302AF is now placed to allow
gravity defueling. During defuel, the fuel flows through the 302AF to a separate defueling line back to
the defuel tank. NOTE: Most Air Force bases have modified their Panero systems (filter meter pits) to
use MH2-series hose carts. This modification consists of removing the meter and micronic filter from
the filter meter pit and installing pipe spools in their places.
4.4. System Components.
4.4.1. Deep-Well Turbine Pump (Vertical). Each underground operating storage tank has one
1135- or 2271-liter-per-minute (300- or 600-gallon-per-minute) pump. See Chapter 3 for a
description and Chapter 10 for maintenance frequencies.
4.4.2. Nonsurge/Check Valve (81AF).