Hydra-Electric History



Our timeline spans the advance of modern aviation, with landmark developments in commercial travel, military/defense and space exploration.

  • 1948

    Company Founded

    – Allen V.C. Davis invents the first negative rate disc spring, and founds Hydra-Electric. Fuel tank valves are Hydra’s first products.

  • 1950

    First Customer

    – Lockheed becomes Hydra-Electric’s first switch customer.

  • 1952


    – Hydra’s hydraulic pressure switches are utilized on the B-52.

  • 1954

    Boeing 707

    – Boeing purchases Hydra’s switches for the fuel and pneumatic systems of its first jet airliner, the Boeing 707.

  • 1955

    Lockheed U2

    – Lockheed selects Hydra-Electric for the U2, its reconnaissance aircraft nicknamed “the Dragon Lady.”

  • 1958

    Gulfstream I

    – Hydra-Electric provides all pressure switches on the Grumman Gulfstream I, a twin turbo-prop business aircraft.

  • 1961


    – Hydra-Electric develops switches for the Atlas launch vehicle, part of NASA’s Mercury project for human spaceflight in which John Glenn was the first U.S. astronaut to orbit the earth.

  • 1963

    Dassault, Learjet

    – Hydra-Electric products are selected by two pioneering business jet programs – Dassault Falcon 20 and Learjet 23.

  • 1969

    Saturn V Rocket

    – Switches from Hydra-Electric are utilized on the Saturn V rocket used to transport Neil Armstrong and all the other astronauts to the moon. The Company’s products are used as part of the fuel and pneumatic systems, and also as part of the “chicken switches” (devices that allow an astronaut to eject the capsule in which he or she rides in the event that a rocket malfunctions).

  • 1970

    Boeing 747

    – The first wide body jumbo jet, the Boeing 747 incorporates hydraulic and fuel flow switches from Hydra-Electric.

  • 1974

    F-14 Tomcat

    – Hydra-Electric supplies pressure switches for the Grumman F-14 Tomcat.

  • 1975

    Patriot Missile

    – Company’s switch technology is utilized on the Raytheon Patriot Missile (which derived its name from “Phased Array Tracking Radar to Intercept On Target”).

  • 1975

    AH-64 Apache

    – Hydra’s switches are selected for the Army’s AH-64 Apache – a four-blade, twin-engine attack helicopter still in use today.

  • 1981

    F-117A Nighthawk

    – Lockheed F-117A Nighthawk program incorporates Hydra-Electric’s products for its stealth ground-attack aircraft.

  • 1983


    Began providing sensing technology for Embraer, beginning with the EMB 120 and other programs to follow

  • 1987

    Airbus 320

    Hydra’s hydraulic switches are utilized on this commercial aircraft program

  • 1989

    Bell Textron V-22 Osprey

    Hydra-Electric provided numerous different switches for this tiltrotor military aircraft

  • 1991

    McDonnell Douglas C-17

    Hydra-Electric provides sensing instruments including hydraulic switches for this large military transport aircraft

  • 1994

    Eurofighter Typhoon

    Hydra-Electric provides fuel switches for the Eurofighter Typhoon

  • 1997

    Lockheed MARTIN F-22 Raptor

    Hydra-Electric provides high performance sensing technology on this twin-engine, all-weather stealth tactical fighter aircraft developed for the United States Air Force

  • 2006

    Airbus A380

    Hydra-Electric provides high performance sensing instruments for this wide body commercial aircraft program

  • 2009

    Bell 429 GlobalRanger

    Hydra-Electric’s high performance sensors are utilized in the light twin engine helicopter

  • 2011

    Joint Strike Fighter

    The JSF program aircraft are able to take advantage of Hydra-Electric’s breakthrough technology in high performance pressure sensors

  • 2012

    airbus A320NeO

    Hydra-Electric provides engine switches for the A320neo

  • 2013

    Eurofighter Typhoon

    Hydra-Electric provides high performance sensors for the world’s most advanced swing-role combat aircraft

  • 2015

    Pilatus PC-24

    Hydra-Electric provides sensors for the environmental controls system of the Pilatus twin-engine business jet

  • 2016

    RTCA DO-160 Level 5

    Hydra-Electric sensor designs achieve highest level of lightning protection for the most severe electromagnetic environments

  • 2017


    Over 20 of Hydra’s switches and sensors selected for Airbus long haul, twin engine wide-body jet airliner

  • 2018

    Irkut MC-21

    – Completed qualification for sensors of single-aisle twinjet airliner.

  • 2019

    Bell 525 Relentless

    – After years on test aircraft, qualification complete for Hydra-Electric sensors.

Over seven decades ago, Hydra-Electric developed and patented the snap action sensing of pressure by means of the negative rate disc spring, employing an additional trim spring for pressure adjustment. This environmentally superior powered snap action design has since become the standard for critical aerospace applications.

As the sole supplier of negative rate disc spring pressure switches, Hydra-Electric grew quickly furnishing pressure switches for fuel, hydraulic, pneumatic airspeed and barometric (altitude) applications for most high performance jet powered aircraft programs. Hydra-Electric has continued to innovate the negative rate spring and pressure sensing systems, applying its designs to thousands of aircraft and missile systems.

Hydra-Electric has also introduced breakthrough technology in high performance sensors. These patented and patent-pending designs address problems that older technologies cannot.  Download our historical timeline summary, “A Pioneer in Aviation History”