The General Electric ID-14/APN-1 Radio Altimeter Altitude Limit Selector Switch, was a component of the AN/APN-1 radio set, used to measure and indicate to the pilot his altitude over the terrain during flight.
This was particularly critical for USAF and USN aircraft such as the ground-attack light bomber, the Douglas A-26 Invader and the carrier launched, TBF Avenger torpedo bomber and the SB2C Helldiver dive bomber.
The AN/APN-1 was the US military's primary airborne frequency modulated, radar altimeter which was designed to emit a downward signal from the aircraft's transmitter antenna.
As the terrain changed in hight and composition with the rise and fall of the aircraft's flight, a 'bounced' return signal would be received by a separate receiver antenna. The difference in signal frequency and time interval from send and receive gave a highly accurate height reading.
The timing and correct height of torpedo or dive bomb release was crucial to ensure the weapons had enough time to self arm and hit their targets.
The Altitude Selector Switch enabled the pilot or bomb aimer to set the lower altitude limit. If the aircraft descended below this limit a red light would illuminate on the panel while a green light indicated the aircraft was too high. A yellow light indicated the correct selected height.
The centre knob of this instrument still turns to set the altitude between 50 to 300ft and while there is some minor paint chipping on the outside dial, the glass, display and case are in excellent condition.
This Douglas A-26 Invader Instrument comes complete with detailed Scale Model, Mango Wood Stand & Plaque plus Printed Fact Sheet featuring photo of instrument in aircraft cockpit.
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Your Douglas A26 Invader WWII Radio Altitude Limit Switch, Original Recovery Curios Warbird Collectable includes:
- Original Warbird instrument
- Highly detailed hand-built and airbrushed 1/72 plastic scale model of the aircraft,*
- Hand-crafted and beautifully finished 100yr, Far North Queensland Mango Wood display stand
- Detailed, 2-sided, printed and laminated Instrument Fact Sheet detailing aircraft and instrument
- Removable Magnetic Display Arm
* Upsize to the more highly detailed 1/48 scale for just $45. Click on the 1/48 Scale Option at the top of the page.
Both the 1/72 and larger 1/48 scale custom built and airbrushed plastic models are available with 'wheels & flaps up or down' and 'canopy open or closed' options with a choice of two Squadron markings and camouflage.
Upon order placement you will receive an email asking for your preferred configuration.
Your complete Recovery Curios Original Instrument Collectable is securely packed and delivery normally takes between 4 - 6 weeks approx.
Did you fly, crew or maintain a Douglas Invader or have a friend, colleague or family member who did? Check out our PERSONALISED ORIGINAL INSTRUMENT COLLECTABLE OPTION here.