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Manned Aircraft Maintenance Cycles

colinjfischer

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To kick this off I thought I would post about Manned Aircraft maintenance cycles. I think I saw that there is an A&P here so they can tell you more than I as a pilot can.

Basically, commercial general aviation aircraft (part 91) have the following maintenance cycles

100 hour inspection - performed every 100 hours of flight time
Annual Inspection - performed every 12 calendar months

The 100 hour and Annual are nearly identical inspections. An annual can replace a 100-hour, but not vice-versa.

Additionally, the pitot-static systems (airspeed and altitude indicators) need to be serviced every 24 calendar months. The same goes for the transponder (which is used by air traffic control to figure out who and what you are). We also have to have the ELT (emergency locator transmitter, in case we crash someone can find us) every 12 calendar months. Depending on your engine, it will need to be overhauled every 3,000 flight hours (or so).

In 2008 I was part of a team that got a drone FAA-certified, and we had a 25-hour maintenance cycle (so we did the 100-hour every 25 hours). We had a gas engine at the time so it made sense.

As for drones, this time interval might be a little too long. I fly my drones 15 mins to 30 mins at a time, and that seems to be a long flight. A 100-hour inspection might be too long a time interval; but then again there isn't as much to check.

As for equipment replacement, the only figure I can find is that my 3DR Solo motors have a lifespan of approximately 150 flight hours. So I am keeping a logbook of every flight in each of my Solos so I know when to order new motors. Other than performing a pre-flight, replacing props when I need to, and recording new equipment I install (such as a gimbal, etc) I don't have any good maintenance cycle advice.

Taking this info, what can we create that is comparable to the Manned Aircraft cycles, but also cost-effective for us?
 
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May I offer a starter thought. How about a visual inspection before and after each flight. Easy to do and cost effective. Check props for damage, look for cracks on body shell or legs. Remove debris from hull (dead insects etc), check all lights are working correctly, and screws loose ( in the pilot too perhaps? Lol). Check prop mounting, battery mountings.
Certainly I would believe that this is in keeping with full sized aviation, and I do this myself every flight, and record the results.
 
To kick this off I thought I would post about Manned Aircraft maintenance cycles. I think I saw that there is an A&P here so they can tell you more than I as a pilot can.

Basically, commercial general aviation aircraft (part 91) have the following maintenance cycles

100 hour inspection - performed every 100 hours of flight time
Annual Inspection - performed every 12 calendar months

The 100 hour and Annual are nearly identical inspections. An annual can replace a 100-hour, but not vice-versa.

Additionally, the pitot-static systems (airspeed and altitude indicators) need to be serviced every 24 calendar months. The same goes for the transponder (which is used by air traffic control to figure out who and what you are). We also have to have the ELT (emergency locator transmitter, in case we crash someone can find us) every 12 calendar months. Depending on your engine, it will need to be overhauled every 3,000 flight hours (or so).

In 2008 I was part of a team that got a drone FAA-certified, and we had a 25-hour maintenance cycle (so we did the 100-hour every 25 hours). We had a gas engine at the time so it made sense.

As for drones, this time interval might be a little too long. I fly my drones 15 mins to 30 mins at a time, and that seems to be a long flight. A 100-hour inspection might be too long a time interval; but then again there isn't as much to check.

As for equipment replacement, the only figure I can find is that my 3DR Solo motors have a lifespan of approximately 150 flight hours. So I am keeping a logbook of every flight in each of my Solos so I know when to order new motors. Other than performing a pre-flight, replacing props when I need to, and recording new equipment I install (such as a gimbal, etc) I don't have any good maintenance cycle advice.

Taking this info, what can we create that is comparable to the Manned Aircraft cycles, but also cost-effective for us?
Brushless motors have no moving parts so do not have a 'life span' as such.
The only maintenance on the motors would be the bearings which are normally around 100 hours. Fully ceramic are better and will easily give you 5 times that figure!
Regular Airframe inspections are important to look for fatigue and stress cracks and fastenings should be checked/torqued regularly.
A log of battery cycles is important with flight times to determine whether there is a trend of cell deterioration.
Props should be checked before and after every flight and motor temps taken immediately after SOD which will give an early sign of bearing wear.
 
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May I offer a starter thought. How about a visual inspection before and after each flight. Easy to do and cost effective. Check props for damage, look for cracks on body shell or legs. Remove debris from hull (dead insects etc), check all lights are working correctly, and screws loose ( in the pilot too perhaps? Lol). Check prop mounting, battery mountings.
Certainly I would believe that this is in keeping with full sized aviation, and I do this myself every flight, and record the results.

Yeah, I definetly do a 'walk-around' before each flight. I also do the IMSAFE checklist (Illness, Medication, Stress, Alcohol, Fatigue and Emotion or Eating).

Also - I found these mx forms that I made up a while ago. There are programs and apps for that now, but they might be useful to some.
 

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I’m presently doing a ‘walk around’ before each flight. Then monthly I do a complete inspection, documented with a checklist and date of inspection. Many items on the list are performed as part of the ‘walk around’ while others are more detailed.
 
I’m presently doing a ‘walk around’ before each flight. Then monthly I do a complete inspection, documented with a checklist and date of inspection. Many items on the list are performed as part of the ‘walk around’ while others are more detailed.
Do you have a copy of this checklist that you don't mind sharing?
 
Longevity of engines depends on a # of factors. For instance, if you live in a aired place like Arizona or parts of Southern California you're most likely going to get a grains of sand lodged inbetween moving parts of the engine , this will expedite engine failure quicker. Leading edges of blades will wear out faster.
 
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Longevity of engines depends on a # of factors. For instance, if you live in a aired place like Arizona or parts of Southern California you're most likely going to get a grains of sand lodged inbetween moving parts of the engine , this will expedite engine failure quicker. Leading edges of blades will wear out faster.
Here in SC we have lots of sand and loose dirt so I use a 3'x5' landing pad to keep dirt away from my aircraft.
 
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Here in SC we have lots of sand and loose dirt so I use a 3'x5' landing pad to keep dirt away from my aircraft.
I use a folding 4’ table to launch/recover. It will even sit in the back of the truck. Keeps camera out of dirt/sand/grass, as well as engines off the ground. Good Idea Orange Bird!
 
I support and adopt The Editor's comments and note that brushless motors have no moving parts except the bearings and would only
ad one thing regarding maintaining motors which is that I oil them with special oil used by drone racers.
I bought it from Banggood (see photo) and comes with a needle and cerringe which makes it easy. Cheers John
 

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I support and adopt The Editor's comments and note that brushless motors have no moving parts except the bearings and would only
ad one thing regarding maintaining motors which is that I oil them with special oil used by drone racers.
I bought it from Banggood (see photo) and comes with a needle and cerringe which makes it easy. Cheers John
How often do you do that? Is it scheduled, or just as-needed?
 
Hi colinjfischer, Before I answer your questions, I live in Sydney Australia and it gets hot here and have been flying in 40c temperatures so the point is that motors run warmer (oil will dry out with heat). I have oiled all my drones and I can notice a difference "smoother" but it is all done by listenning to the motor sound however in the summer I do a check of motors every 10 hours of flight time and in the winter (here in Oz) about every 15 hours flight time. Also it is not always needed and the oil is only a small drop between the motor shaft and bearing. Be careful the type of oil you use as some contain additives and that's not good I researched bearing oils and I found the one I mentioned good and safe.
I hope I have answered your questions and recommend the oiling but on a managed bases to your flying needs.
Cheers, John
 
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How does the oil do as far as slinging out and collecting dust, etc. Do they stay ‘clean’?
 
Hi rvrrat14, It is applied with a very thin needle ceringe and only a couple of small drops where the motor shaft meets the
bearing. I have not had any issue with excess or slinging at all. Naturally you don't over do the oil it's always best a little at
a time. Cheers John
 
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Hi Sojourner60, That is a very difficult question to answer however what I can tell you is that i have a Phantom 3 Advance and have clocked 175 flight hours and still going strong. With care my opinion these Brushless motors will last a very long time. Cheers, John
 
Hi Sojourner60, That is a very difficult question to answer however what I can tell you is that i have a Phantom 3 Advance and have clocked 175 flight hours and still going strong. With care my opinion these Brushless motors will last a very long time. Cheers, John
Do you blow the motor housing/motors out with air?
 
Thanks John! I'm logging my flights. I've only got about 2 hours on it. I'm a little concerned about one motor. It has a high pitched squeal when I turn off the motors. I'm hard if hearing and I can hear it. I'm thinking it may have gone away. I don't remember hearing it the last time I turned off the motors.
 
Hi Sojourner, It could be several reasons but I strongly believe it is a dry bearing and would certainly recommend as soon as you can oil the bearing but first blow the motor with clean air ( as per computer pressure can air). I have never blown my motors with air but I don't fly near any dust or sand and the spinning propellers will do that job.
Cheers, John
 
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