"There is hardly anything in the world that some man cannot make a little worse and sell a little cheaper, and the people who consider price only are this man's lawful prey."
- John Ruskin
Midwest's Overhaul Philosophy
We know that many potential customers are apprehensive about purchasing a Robinson helicopter that has been overhauled in the field by an Authorized Service Center. There are countless ways to cut corners on a Field Overhaul. Midwest doesn't do any of those. Midwest has been completing first-class overhauls for more than 10 years. Some overhaul facilities only overhaul or purchase selected overhaul exchange components from the factory. Midwest only buys the complete factory overhaul kit (including fuel bladder tanks, if required) and properly installs, tests, aligns, and rigs all of the items supplied in the Robinson factory overhaul kit.
What was in the RHC Factory-Supplied Overhaul Kit for our most recent overhaul (N646MS, Raven I) as an example:
Brand-New Robinson Factory Parts Installed at Overhaul
- Both '-7' Main Rotor Blade and Spindle Assemblies*
- Both Tail Rotor Blades and Hub Assembly
- Main Rotor Gearbox*
- Upper Sprag Clutch, Belt Sheave, Bearing and Shaft Assembly*
- Electric Clutch Actuator (Belt Tensioner) Assembly*
- Welded Upper Frame
- Swashplate Assembly with New Pitch Links and All New Hardware*
- Main Rotor Hub with Bearings, Main Rotor Hinge Bolts, & Droop-Stop Parts
- Tail Rotor Driveshaft and T/R Gearbox Push-Pull Tube
- Tail Rotor Pitch Control with Bearing
- Tail Rotor Pitch Links and Bellcrank Assembly
- Tail Rotor Guard
- 4 New Drive Belts, Alternator Belt, and All 10 Air Duct Cooling Hoses
- Lower Fan Shaft and Bearing Assembly
- All 3 Driveline Flexplates
- 4 Elastic (Bungee) Cords
- All 4 New Seat Belts & Buckles
- Complete Factory Engine "Quiet" Exhaust System & Carb Heat Scoop
NOTE *In some overhaul kits, these items are supplied from the factory in the overhaul kit as factory-overhauled components, while in other cases Robinson provides brand-new parts.
Robinson Factory-Overhauled Parts Installed at Overhaul
- Hydraulic Pump, Reservoir, and All 3 Servos
- Tail Rotor Gearbox Assembly
- Dual Engine / Main Rotor Tachometer
- Governor Controller
- Fanwheel Assembly
Overhauled Engine from Signature Engines, Inc.
- Major Engine Overhaul with all Lycoming ADs and Service Bulletins Complied With
- 6 Brand-New Lycoming Cylinders with Valves, Valve Springs, etc.
- Overhauled Magnetos
- Overhauled Carburetor or Fuel-Injection Servo System
- New Spark Plugs and Plug Wire Harnesses
- New Flywheel Starter Ring Gear Installed
- Engine Dynamometer-Run-In and Performance Check
OR
Lycoming "Zero Time" Factory-Remanufactured Engine
In order to comply with the latest ADs and Survice Bulletins, in some cases Midwest Aeronautical may install a "zero-time" Lycoming O-540-F1B5 or O-540-AEIA5 factory-remanufactured engine. In these cases, the engine will include:
- Brand new crankshaft, cylinders, roller cams & tappets
- Brand new magnetos, carburetor, alternator, starter, battery & flywheel ring gear
- Includes new engine logbook, considered as a "new" engine under FAA regulations
- (All items above are brand new from Lycoming, not overhauled parts)
What is done on a proper Midwest Aeronautical R44 overhaul?
Disassembly
First of all, the helicopter is completely disassembly down to the bare cabin sitting on the skids. During disassembly, all parts are thoroughly inspected and a list is made of additional parts that need to be replaced during reassembly based on normal wear and tear above and beyond those supplied in the factory-overhaul kit.
After disassembly, all the "core" items (items that will be overhauled at the factory and used in future overhaul kits) are shipped back to Robinson for evaluation and credit.
Then, a complete Factory overhaul kit is ordered and paid for in advance (including bladder tanks if required). Current price for that kit is $141,000.00 plus a Core Charge Deposit of $40,000.00. This does NOT include the cost of the engine overhaul, presently approx. $36,000.00.
Other parts and supplies are ordered to replace worn items or to comply with Airworthiness Directives (ADs) and Factory Service Bulletins that need to be performed.
Then, the lower structural frames are removed and sent out for bead blasting to bare metal, magnetic particle inspection, and two powder coats applied (primer and finish coat).
All sheet metal parts are evaluated and repaired or replaced as necessary.
Reassembly, Rigging, and Testing
All work is done in accordance with the procedures outlined in the Robinson Maintenance Manual. (It normally takes Midwest about 3 months to do a first-class overhaul from start to finish).
Midwest always supplies new Airframe and Engine Logbooks and a Current Pilot Operating Handbook (POH), along with a new Hobbs Hour meter to record flight time since overhaul.
All ADs and Service Bulletins are researched and complied with. Battery, Starter, and Alternator are evaluated and replaced if necessary. Skid shoes are inspected and replaced if necessary.
Hydraulic flight control systems are installed with new packings, etc. and pressure-tested.
Normally, new leather interior Seats are installed along with new floor carpeting, etc. This cost is in addition to the overhaul kit and engine overhaul cost.
After the helicopter is completely reassembled, the tail rotor and main rotor systems are "rigged" in accordance with the procedures called for in the Robinson Maintenance Manual.
After the first engine-start, the engine cooling fan, tail rotor assembly, and main rotor assembly are tracked and balanced.
During several hours of break-in and test-flights, the radios, instruments, gauges, and avionics are evaluated and overhauled or replaced as required.
All work performed is properly entered in the new 'post-overhaul' engine and airframe logbooks.
This is the RIGHT WAY to do an overhaul, and Midwest does them RIGHT !!
