Title of the invention Drop Tank Fuel Transfer Simulation Test Kit for a Fighter Aircraft
Field of invention
The field of invention is in the Overhauling of Fighter aircraft and the invention is a methodology for testing the health parameters of fuel system, wiring and Line Replaceable Units on a Fighter/Trainer aircraft prior to the fitment of External Drop Tanks on both wings.
Use of invention
This invention is used to check the serviceability of the fuel transfer system in aircraft (pertaining to Drop tank transfer and its indications) before fitment of drop tank on aircraft during Overhauling/Major servicing.
Prior art
There was no methodology for testing the health of fuel transfer system mainly the effectiveness of wiring system and its associated LRUs for fuel transfer prior to fitment /installation of Drop tank to the aircraft during Overhauling. Snags generated were not traceable before fitment on aircraft.
Draw backs of prior art
There was no prior art facility available in the Division for testing the health of fuel transfer system, mainly the effectiveness of fuel transfer wiring and LRUs prior to fitment /installation of Drop Tank to the aircraft during Overhauling. However, the Drop tank fuel transfer was checked for functional operations and its indications directly by fitment on aircraft. Thereby involving major man hours and man days to rectify the snags.

Comparison between prior art and present invention
There was no prior art (test kit) facility available in the Division for testing the health of fuel transfer system mainly the effectiveness of fuel transfer wiring and LRUs prior to fitment /installation of Drop Tank to the aircraft during Overhauling of the same. Drop tanks removed from aircraft were sent to the manufacturing Division for functional checking.
In the invented (present invention) method, the identification of the snags of fuel transfer is being evaluated by way of indications shown in the Magnetic Indicator. During the process of fuel transfer from External tank, float valve allows the fuel transfer to external tank from positions RL1, RL2 and RLF to transfer to F2 and F3 tank by Air pressure. And during the fuel transfer to External Drop tank, the high level float and low level float will indicate in the Magnetic indicator with Black strip and considered as Full, while indications shown in the Magnetic Indicator is white which is considered as External Drop tank empty Aim of the invention
Simulation of drop tank fuel transfer checks on Fighter and Trainer aircraft to confirm the serviceability of aircraft wiring, LRUs and indications in the cockpit.
Summary of the Present Invention
A New test kit has been developed with a new set of wiring by synchronizing with the indications parallel with the Magnetic indicator in the cockpit. The simulation can be carried out on-ground without disturbing the aircraft systems and avoiding the cross-functional checks with other systems of the aircraft when aircraft is fully built-in condition. This new test kit will simulate with simple indications of Red and Green lights referring to the availability and non-availability of fuel content on aircraft and External Drop tank. Thereby, confirming the serviceability of fuel transfer system on both aircraft and externally fitted drop tank.

Brief description of drawings
FIG.1 Illustrates the Circuit diagram of the invented test kit
FIG.2 Illustrates the Fuel Tank Positions on the aircraft.
FIG.3 Illustrates the Front panel of the invented Drop Tank Test Kit FIG.4 Illustrates the Internal circuitry structure of the invented test kit FIG.5 Illustrates the Looms required for connecting to aircraft from the
invented test kit for simulation
Statement of invention
Development of a new Simulation system on ground through a Test kit to diagnose the snags related to fuel transfer on both aircraft side and externally fitted Drop tank.
1. Detailed description of invention
The newly invented test kit when connected to the Externally fitted Drop tank and to the aircraft, functional checks with various types of indications are observed. Based on the Port and Starboard External Drop tank Selections;
> When Switched ON; the Magnetic Indicator in cockpit instrument panel will indicate with white stripes.
> When Switched OFF; the Magnetic Indicator in cockpit instrument panel will indicate white refers to Emptiness in the tanks. Similarly; After fuelling the aircraft and drop tank, the simulator when;
> Switch ON; the Magnetic Indicator in cockpit instrument panel will indicate with black stripes refers to the tanks are full.
> Switch OFF; the Magnetic Indicator in cockpit instrument panel will indicate with black stripes refers to the tanks are full. „ „

Also the refueling method being carried out on the aircraft are with hatch identification methodology:-
> Switch ON, the Magnetic Indicator in cockpit instrument panel hatch flow
> Switch OFF Magnetic Indicator in cockpit instrument panel hatch flow
> Switch ON, the Refuel defuel panel indication RL1 RL2 indicates in ON condition
> Switch Off, the Refuel defuel panel indication RL1 RL2 indicates in ON condition.
Alternatively,
> Switch ON, the Refuel defuel panel indication RL1 RL2 indicates with OFF
> Switch OFF, the Refuel defuel panel indication RL1 RL2 indicates with OFF
The newly invented test kit was connected with the externally fitted Drop tank for simulation test kit by connecting to the junction Module of 137A and 138A on Port and Starboard Leading Edge of the Wing Assembly on the Fighter/Trainer aircraft. Aircraft fuel system pertaining to drop tank transfer and indication before fitment of Drop tank on Aircraft. In Fighter aircraft a float valve allows the fuel transfer from external tanks RL1, RL2 and RLF tanks F2 and F3 by air pressure via fuel valves RL1, RL2 and RLF respectively and hence via TRL.
As fuel is drawn from external tank high level float switches in each change over switch RL1 RL2 RLF magnetic indicators shows full black indication when external tanks is empty, the low level float switch in each tank. RL1 RL2, magnetic indication show white indication.
The snags in aircraft side arising when the drop tank is fitted with full fuel, where as the indication shows white suppose to black and while transfer working. At present to identify these type of snags, no test kit is developed to confirm the snags on aircraft or external tanks. Drop tank simulation test kit when connected

to aircraft through 137 Delta connector (Port Wing Leading Edge) and shorting connector to 138 Delta (Starboard wing leading edge)
Open the Refuel / Defuel panel, check the RL1 light in the refuel / defuel panel is 'ON' and check the Magnetic Indicator in cockpit RH instrument panel shows Hash indications.
The indications in the newly developed/invented test kit is identified with Red and Green colour LED lights referring to Red as Emptiness of fuel and Green as Tank is full and simultaneously cross checked with the Black and White stripes indication in the cockpit on the Magnetic indicator by positioning a personnel in the cockpit and a personel on the Ground, which is a tedious process and lot of time consuming and reliability on functionality of Magnetic indicator is also verified by this newly invented test it.
Hence, double check is involved and ensures the functional aspects are proved on the effectiveness of fuel transfer obtained on the aircraft and also there by immense satisfaction and confidence is achieved.

Claims
We claim
1. Indigenous Design and Development of a New test kit with all the necessary circuit diagrams. .
2. Lay out of front panel of the test kit is designed and executed.