Another problem area is in engines with crank counterweights, a very common design. Definition of Propeller Strike (i) For the purposes of this AD, a propeller strike is defined as follows: (1) Any incident, whether or not the engine is operating, that requires repair to the propeller other than minor dressing of the blades.
What to Know About Part 139 SMS for Airports, 8 Decisions Amsterdam Airport Schiphol Says Will Lead to Quieter, Cleaner Aviation -- Including No More Private Jets, TSA Begins Process To Federalize Security Operations at Jackson Hole Airport, Phillip A. Washington Statement, Withdraw from FAA Nomination, Transportation Security Administration (TSA). According to DeJoris, "Hartzell requires hub replacement if any blade in the assembly is bent beyond repair limits due to impact damage. Aircraft Owners & Pilots Association Find it free on the store. Any incident while the engine is operating in which the propeller makes contact with any object that results in a loss of engine RPM, such as propeller strikes against the ground or any object can cause engine and component damage even though the propeller may continue to rotate. Propeller inspections are fairly clear cut damage on the blades is typically quite apparent, and the existence of damage beyond field repair limits dictates that the unit is disassembled and given a searching internal inspection, and in some cases, complete overhaul. A Textron Lycoming engine, that is being operated on a Part 91 aircraft, that had a sudden engine stoppage, not a propeller strike, must comply with A.D. note 91-14-22 and Service Bulletin 475B at a minimum. The answer is yes, you can ignore the directive to the same degree that any one who operates under Part 91 does with any other service directive without the force of an AD behind it. How much liability insurance do you have? WebAD/PROP/1 Amdt 2 (continued) Page 6 of 9 HOFFMAN (continued) Continental IO-346 engines 1000 All other Fixed Pitch Types 2000 Flottorp storage, overspeed, ground strike or aerobatic requirements refer mt-propeller Service Bulletin 1 Revision X. According to Lycoming, this is what's considered a prop strike: Prop strikes can occur during anything from a hangar door hitting a stationary aircraft (without the engine running), to a gear-up landing. 0000008269 00000 n As for whether the inspection should be done, Anderson said he couldn't answer for anyone but himself; however, he wouldn't hesitate if it were his engine. This could indicate a gear-up landing, or other source of damage that took time to fix. But as they came back to land, deer started running across the runway as the pilots touched down in their Cessna 182. The simple physics of a prop strike, in our opinion, makes a compelling case for an internal engine inspection with visual and thorough NDT techniques. Diurnal meaning, "daytime," these types of winds follow a set schedule that reacts to the earth's solar heating every day. Why Does Maneuvering Speed Change With Weight? They are often ignored in the prop-strike evaluation, yet they have prescribed inspection criteria even if involved in only a sudden stoppage. That NPRM contained the SFP paragraph, although it should have been removed, based on the FAR 39 rule change. 0000001350 00000 n
Start your free trial today! All rights reserved. The dowel pointed to in the picture below is in the crankshaft on the opposite end from the propeller. 75 0 obj <> endobj The prop had a good-size dent in it, prompting the pilot to remove the prop and send it in for repair.
0000003565 00000 n Inspect all engine driven accessories in accordance with the manufacturers maintenance instructions. On TCM engines with the geared alternators up front, he has seen the mounting flange and the gear drive bolts break during a prop strike.
Use as-is but guaranteed to not rejected if sent to Divco Contact Thomas Wottreng, Owner - located Elkhorn, WI 53121 United States Telephone: That said, you'll understand that this article isn't going to state, or even hint at, what you should do in this situation. But let me start this section with a caveat: There is no black and white, and the subject under discussion is the grayest of the gray areas. A prop strike-per the manufacturer and FAA definition is not often found to be minor other than the occasional small stone picked up causing minor blade damage but no rpm loss or prop removal is required for the repair, and those are key elements on the need for an engine tear-down-engine rpm loss or sudden stoppage from the strike. z}YSv A0Lm1wE@ O+>T7])o,dZF|M*ZmWdQsj ~cf#0ZDcVqvHT0 @q9lz;0P90]lfzy5j@
44 0 obj<>stream 0000007131 00000 n DeJoris, who deals with propeller strike issues quite frequently says, "We recently had a customer with a prop strike who struck a steel stake that cut 1/4-inch of the tip off one blade of a three bladed prop. 88 0 obj <>/Filter/FlateDecode/ID[]/Index[75 20]/Info 74 0 R/Length 71/Prev 16864/Root 76 0 R/Size 95/Type/XRef/W[1 2 1]>>stream Plus, unless you were watching the tach, how would you know?
According to John DeJoris, president of Aircraft Propeller Service Inc., in Wheeling, IL, "The FAA has embraced the policy that any type of propeller strike is a cause for teardown and engine manufacturers are quickly jumping on board.
This damage can result in catastrophic engine failure. http://forums.aopa.org/showthread.php?t=12483&page=3&highlight=walk+prop, (You must log in or sign up to reply here. Home; About; Surrogacy. WebDoing an engine teardown after a prop strike is as close to a no-brainer as these things get.
WebDefinition of Propeller Strike (i) For the purposes of this AD, a propeller strike is defined as follows: (1) Any incident, whether or not the engine is operating, that requires repair to
They were legitimate, having been initiated after an inspection, but that doesn't help when selling the airplane. If it has, and there's no indication in the engine logs about a teardown and inspection, it's time for a long explanation from the seller. Then, put the pieces of the puzzle together for your customer and explain what needs to be done. Ken Tunnel of Lycon Aircraft Engines in Visalia, California, an engine facility used by a number of owners of show airplanes, said, "There's no way you can tell if there's any damage regardless of the circumstances.
Moreover, the crank is not the only critical element in a prop-strike incident. Also, on prop strikes involving frontal impact, the crank can be pushed back into the engine, cracking the case at the slinger ring, and this may not be visible. Surrogacy Cost in Georgia; Surrogacy Laws in Georgia; Surrogacy Centre in Georgia; Surrogacy Procedure in Georgia You will note TCM does not get into the concept of sudden stoppages possibly being handled differently as Lycoming does. A prop strike is a rotating prop hitting an object that causes a speed variation (NO stoppage) and blade damage, OR a stationary prop is hit by a moving object that causes blade damage. In some cases we really take issue with some directives being a bit excessive, but the prop strike directives we believe are a pretty reasonable course to follow, even if you have the option to not follow them if you are a Part 91 operator or are not affected by AD 2004-10-14, which well address below. Secure the airplane and figure that it will be out of commission for a few months. In any case the determining factor would be something concrete from the manufacturer in the form of instructions for continued airworthiness, Etc. Here's a picture of a Lycoming engine with the accessory case removed. We did a prop strike %%EOF
In the forced landing last February, my prop hit the parked Piper. ;T%U2C]b(evh)-f;x%q-t KB4U\LePK!UOJ]I UC.Mq%>Cmp,Gw9.en:B*`1 McCauley hubs must be retired if any of the blades within the assembly are bent beyond repair limits inboard of the 85 percent blade radius. It defines a sudden engine stoppage as; stopping an engine in one revolution or less for any reason, be it from propeller impact or from an engine failure of some sort.
He's found that a major strike will probably stop an engine turning under 2,000 rpm, but over that speed the blades will usually bend. Adverse yaw is the tendency of an airplane to yaw in the opposite direction of the turn. 0000001141 00000 n I alluded to the potential of buying an airplane that suffered a prop strike without the required inspections being completed.
Textron Lycoming has also published Service Bulletin 475B which requires, in the event that the engine has experienced a propeller strike, inspection and possible rework of the accessory gear train as well as the rear of the engine's crankshaft. If you need someone to remove and reinstall the engine, that's another $1,800.
Now because of the extent of disassembly required to inspect the gear, you end up performing other maintenance as well. Prior to any ground operation of the engine assure that the propeller flange and the crankshaft flange area are free of any crack indications in addition to the engine component inspection. 0000002085 00000 n 0000007261 00000 n
Mahlon Russell, production manager for Mattituck Aviation Corporation, an engine overhauler in Mattituck, NY, says, "The only pertinent FAA definition that I have been able to find for sudden stoppage' is in Advisory Circular 43.13-1A.
Its not a smoking gun, but perusing the accident reports makes one wonder about such coincidences.
My investigation started with my need for another engine for my Cessna 210. No more filing blades a bit shorter after a tip strike, or performing a run-up and signing off on an engine after the runway lights have been mowed a bit shorter. Bending loads alone are not the only destructive element, and nondestructive testing of the entire crank and associated structures is the only reasonable way to check it out. The accident was recorded on video and available on the Internet.
The one that came with the airplane had passed TBO (time between overhauls) but its logbooks didn't go back to when it came from the factory. But what is a prop strike and what exactly are the ramifications? There's also the cost of inspection of the accessories, which is extra. There's a tremendous amount of energy stored in the rotating flyweight, and when all of a sudden you stop the prop and engine, that energy has to be dissipated somewhere.". In addition, propeller strikes also include situations where an aircraft is stationary and a landing gear collapse occurs causing one or more blades to be bent, or where a hangar door (or other object) hits the propeller blade.
What this all boils down to is that in the case of any accidental damage to a propeller installed on a aircraft operating under Part 91 of the FARs, it is up to the inspecting mechanic to determine if the engine should continue in service without total disassembly and inspection, or only the SB 475C level of inspection if a Lycoming engine falls into that category. Propeller strike inspections. Prop strike inspections include an incoming Still others will only pay for the labor to do the job and will not pay for any parts. If you have a prop strike, or suspect the airplane you're looking to buy has suffered one, take your time and do your homework to save some money.
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