US3797308A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Aircraft landing altimeter
Assignee: Individual
•
Filing: 1972-11-06
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Granted: 1974-03-19
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Expires: 1992-11-06
Abstract
Abstract An aircraft landing altimeter is obtained for indicating height above touchdown of a landing aircraft after passing a known distance and known height from touchdown point. The indicator pointer responds to static atmospheric pressure difference between the touchdown point and that along the glide slope (ILS) at a selected marker beacon site.
Inventors
- 👤 C Crane
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:46
CPC Classifications
G; G01; G01C; G01C5/00; G01C5/06
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
263 words
In an aircraft height-above-touchdown indicating system, a differential pressure gage having an indicating pointer positioned adjacent a rotatable dial calibrated in units of height, an aircraft supporting said differential pressure gage, a marker beacon receiver supported within said aircraft, a glide slope receiver supported within said aircraft for the purpose of providing glide slope guidance to the pilot of said aircraft, a flexible wall diaphragm supported within said differential pressure gage case, said case having airtight construction with an outlet, said outlet connected by a tube leading to the interior of said diaphragm, said tube having a flexible portion and provided with a Tconnection having a first branch leading to the static pressure system of sair aircraft in order to provide equal static pressure to said case interior as well as to the interior of said diaphragm; a solenoid positioned adjacent said flexible portion of said tube, said solenoid having a moving armature extension arranged to clamp said flexible portion at a locus between said outlet of said case and said T-connection; and electric relay and switching means for activating said solenoid when said aircraft supported beacon receiver is activated in response to a ground based marker beacon transmitter, linkage mechanism between said flexible diaphragm of the differential pressure gage and said indicating pointer to activate said pointer at the activation of said marker beacon receiver in order to indicate differential pressure change as a function of changing height of said aircraft with relation to the static pressure extant within said airtight case of said differential pressure gage after activation of said solenoid.
Claim 2
Dependent Claim
263 words
In an aircraft height-above-touchdown indicating system, a differential pressure gage having an indicating pointer positioned adjacent a rotatable dial calibrated in units of height, an aircraft supporting said differential pressure gage, a marker beacon receiver supported within said aircraft, a glide slope receiver supported within said aircraft for the purpose of providing glide slope guidance to the pilot of said aircraft, a flexible wall diaphragm supported within said differential pressure gage case, said case having airtight construction with an outlet, said outlet connected by a tube leading to the interior of said diaphragm, said tube having a flexible portion and provided with a Tconnection having a first branch leading to the static pressure system of sair aircraft in order to provide equal static pressure to said case interior as well as to the interior of said diaphragm; a solenoid positioned adjacent said flexible portion of said tube, said solenoid having a moving armature extension arranged to clamp said flexible portion at a locus between said outlet of said case and said T-connection; and electric relay and switching means for activating said solenoid when said aircraft supported beacon receiver is activated in response to a ground based marker beacon transmitter, linkage mechanism between said flexible diaphragm of the differential pressure gage and said indicating pointer to activate said pointer at the activation of said marker beacon receiver in order to indicate differential pressure change as a function of changing height of said aircraft with relation to the static pressure extant within said airtight case of said differential pressure gage after activation of said solenoid.
Claim 3
Dependent Claim
190 words
The system of claim 1, with associated radio marker beacon receiver and associated glide slope receiver and with electro-mechanical valve means for selectively maintaining static pressure within said case of said differential pressure gage, a ground based glide slope transmitter, relay means for controlling said electromechanical valve means in response to energy impulse output from said marker beacon receiver, an associated ground based marker beacon transmitter selectively co-located along the transmitted space pattern of said glide slope transmitter in order to define a locus in space above an aircraft landing runway that defines the locus of activation of said electromechanical valve means in order to maintain in said case the atmospheric static pressure existing about said aircraft upon closing of said electro-mechanical valve, and a photocell, a lamp source of illumination, a moving arm made responsive to movement of said diaphragm, a shutter means attached to said moving arm for controlling the amount of light reaching said photocell from said lamp and electric meter means for indicating said photocell current, and said meter means calibrated in units of height proportional to the differential pressure existing in said differential pressure gage.
Claim 4
Dependent Claim
129 words
The system of claim 2, having a zero-center electric meter having a pointer supported shutter, said shutter co-located with the shutter supported on the driven arm of the diaphragm of the differential pressure gage, said zero center electric meter made responsive to the output of said glide slope receiver in order to vary the exposed sensitive area of said photocell to the light source in proportion to the positive or negative current flow through said zero center electric meter, the current being proportional to the aircraft position with respect to the glide path, brake means for holding the instant position of said zero center electric meter movement at the time of activation of the electromechanical valve, and means for relasing said brake means upon deactivation of the electromechanical valve.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-03-18 | 1977-09-17 | 1978-03-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-18 | 1981-09-17 | 1982-03-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-18 | 1985-09-17 | 1986-03-19 | $7700.00 | Window Closed / Lapsed |