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073-08500 – Cleveland (Parker Hannifin) FAA-PMA Pressure Plate Assembly
Available now through the AirParts Aero marketplace.
Overview Section
The Cleveland 073-08500 is a high-strength Pressure Plate Assembly engineered for several popular general aviation aircraft braking systems. Manufactured by Parker Hannifin (Cleveland Wheels & Brakes), this FAA-PMA approved component is the movable plate within the brake caliper that transmits hydraulic force from the piston to the brake lining (pads).
This specific assembly is a critical wear item in the 30-series and 199-series brake configurations. It ensures even pressure distribution across the brake disc, preventing uneven lining wear and ensuring consistent stopping power. The 073-08500 is typically characterized by its two-anchor pin configuration, which provides superior stability and prevents the plate from "cocking" during heavy braking events.
Key Features Section
FAA-PMA Certified: Meets or exceeds all Original Equipment Manufacturer (OEM) standards for structural integrity and thermal performance on certified aircraft.
High-Integrity Forged Aluminum: Constructed from premium alloy to withstand the immense mechanical clamping forces and thermal loads generated during landing rollout.
Dual Anchor Pin Design: Features precision-machined holes for anchor pins (usually the 069 series), ensuring perfectly linear travel and preventing caliper binding.
Corrosion-Resistant Coating: Typically finished with a specialized anodized or cadmium-plated surface to resist the corrosive effects of de-icing fluids, moisture, and road salt.
Precision Friction Interface: The contact surface is machined to a specific flatness tolerance to ensure 100% surface contact with the brake lining (e.g., 066-10500 or 066-06200 linings).
Optimized Heat Dissipation: Designed with a specific mass and surface area to help pull heat away from the hydraulic piston and seals, extending the life of the O-rings.
Technical Specifications Section
| Specification | Detail |
| Part Number | 073-08500 |
| Manufacturer | Cleveland Wheels & Brakes (Parker Hannifin) |
| Certification | FAA-PMA |
| Common Caliper Series | 30-52, 30-63, 199-series |
| Number of Anchor Pins | 2 |
| Compatible Lining | Cleveland 066-10500 (standard 2-hole) |
| Material | Forged Aluminum Alloy |
Aircraft Compatibility Section
The 073-08500 is a standard component for many general aviation mainstays:
Cessna 172 (M, N, P, R, S models): A standard replacement part for the main gear braking systems.
Cessna 182 Skylane: Vital for the high-energy braking required for short-field operations.
Piper Cherokee / Archer / Warrior: Found in many PA-28 wheel and brake conversions.
Beechcraft Bonanza / Baron: Utilized in specific high-performance Cleveland brake STC upgrades.
Mooney M20 Series: Used for its compact, high-strength-to-weight profile.
Technical Applications & Safety
The pressure plate is the primary bridge between the hydraulic piston and the brake disc. If the plate is warped or the anchor pin holes are elongated, the brake linings will wear at an angle, leading to "spongy" pedals and reduced braking effectiveness.
Safety Warning: Inspect anchor pins for "stepping" or grooves. If the pins that hold the 073-08500 are worn, the pressure plate will stick, causing the brakes to drag. This leads to excessive heat, which can ignite a tire fire or melt the piston O-rings. During installation, ensure the pressure plate slides freely on the pins before attaching the linings.
Technical Engineering Insight
The engineering value of the 073-08500 lies in its Parallelism and Torsional Stiffness. In a floating-caliper system, the pressure plate must remain perfectly parallel to the brake disc under thousands of pounds of clamping force. If the plate flexes, the hydraulic piston will extend unevenly, causing localized "hot spots" on the disc. Cleveland engineers the 073-08500 with a specific web thickness to ensure that the force from the piston is distributed equally across the entire surface of the lining, which maximizes the life of the brake disc and prevents the "chatter" often felt during high-speed braking.
Installation & Maintenance Addendum
Anchor Pin Lubrication: Only use a dry-film lubricant (like LPS 1 or a specialized dry silicone) on the anchor pins. Never use grease or oil, as these will attract runway grit and turn into an abrasive paste that will destroy the 073-08500’s mounting holes.
Rivet Inspection: When attaching new linings to the pressure plate, ensure the rivets (usually 105-00200) are set correctly using a specialized brake rivet tool. A loose rivet will allow the lining to shift, damaging the pressure plate's mounting holes.
Flatness Check: During every tire change, place the 073-08500 on a flat surface plate. If a 0.005" feeler gauge can pass under any edge, the plate is warped from excessive heat and should be replaced.
