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Aircraft Maintenance for Jump Aircraft; (Your Thoughts)

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I am starting this new thread for everyone to voice their thoughts on aircraft maintenance as it pertains to jump aircraft.
Many of the posts on "Incidents" end up going out on tangents unrelated to the original incident. For example the Mt. Vernon accident. Yes, the aircraft should not of been flying, but the prior lack of maintenace did not cause the accident. It was the pilot's lack of ability to maintain proper airspeed which led to the stall-spin. Let's stick to that on that post.
Here I would like to open up a discussion on the maintenance side of this incident & other concerns about maintnenance.
I know my profile is blank, so here is some info on myself.
I am an A&P of 15 years with my IA. I worked for numerous years on jump aircraft from 182s to Twin Otters. I was Assistant Director of Maintenance for Seaborne Airlines for a time. They are a 121 operator running Twin Otters on Floats. I am currently Assistant Director of MX/Shop Supervisor for a 135 operator running Turbine Single Otters & Beavers.
I am no longer a current skydiver, sold my gear, so I do not have any ties to the jump industry. Hopefully this means that my replies can be unbias and factual.
I am more than happy to share my knowlodge with anyone who has a question and also my experiences of running a maintenance shop for jump aircraft.

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jump aircraft are runhard! I think that they should be kept on a 100hr maintenance cycle, I think that anyone who did this would find that it's less expensive to maintain this way because components that are wearing or starting to fail get caught sooner before they become a major problem.
Experience is a difficult teacher, she gives you the test first and the lesson afterward

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Hmmm, You're the expert. What's your opinion on jumpship maintenance?
And why are you asking for opinions here, where most people that post don't know a turbine from a radial?


I would not call myself an expert, maybe just qualified to answer questions.
I started this thread because there seems to be a lack of understanding, on a whole, as to the maintenance requirements, regs and just plain general knowlodge of maintaining Part 91 aircraft for jumping.
I was not asking for opinions, though I shall take them, I was asking for thoughts and qeustions concerning this issue, which these days seem to be on a lot of peoples minds.

As to my opinion on jumpship maintenance:
There are a few operators that will go to great lengths to properly maintain there aircraft.
There are many that do just what is necessary to keep the aircraft airworthy.
The dropzone that I was at use to lease an Otter. It was at the DZ all summer, flying 6-7 days a week, putting 10-20 hours a week on the aircraft. It never left the DZ. Mechanics from the lessor never came to the DZ. The season ran for approximately 27 weeks. That works out to 270-540 hours for the season. The inspection interval for an Otter is every 125 hours. Needless to say we stopped leasing.

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Now you are "speaking in tongues" to most here.
Everyone that knows what Part 91 is raise your hand(before googling it!).
This has been discussed here in the past. As in all types of business entities, there are some great maintenance programs and some shoddy ones at DZ's around the globe.
I always encourage jumpers to discuss their own DZ aircraft maintenance with the DZO and other staff.
If it doesn't seem to be good, go to another DZ that is.
The problem is, most jumpers don't even know what color their reserve canopy is, and you want them to debate maintenance schedules?;)
What DZ ran that otter into the ground? I'll make sure I don't leap there anytime soon.:P

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Everyone that knows what Part 91 is raise your hand(before googling it!).



You are correct. Many do not know. That is why I posted this thread. To help make them more aware, answer questions.
You are also correct that many people don't give a shit. The old saying, "Why would anyone jump out of a perfectly good airplane?". But there are a few that do, and that number seems to be growing following the recent events.
Can you please show me where I made the remark that I want to debate MX schedules?
I also thought that these forms were to discuss topics like this to make the average person more knowlodgeable about the sport and what goes on around it. I've never seen anyone slam diverdriver for giving his pilot's perspective.

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Hmmm, You're the expert. What's your opinion on jumpship maintenance?
And why are you asking for opinions here, where most people that post don't know a turbine from a radial?



They are both round and they drag airplanes through the air, what else is there to know? :)

Just burning a hole in the sky.....

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I'm not upset at all, just not sure what you are looking for. And jumpers DO give a shit, no one wants to crash. It's just that many don't know or have a clue what is involved in aircraft maintenance. And you expressed your concern over the otter flying a ton of time without a 125 hr check. That's debating MX schedules. I aksed what DZ it was so I don't have to bail at 500ft someday there.
The problem with debating MX schedules or the such is that a lot of hearsay, not known facts get drug into the conversation. As for diverdriver, he usually gives facts, reports, opinions on specific items. You are asking for jumpers thoughts here on jump aircraft maintenance. That's a shotgun approach. I'm just not sure what you want thoughts on? Here's my take. I jump at Perris and do business with them. I spend a lot of time with Pat in the hangar asking stupid questions. 99% of the other jumpers have never even been by the hangar unless they have a bad spot. That's good too. Otherwise no work would get done in there. Whenever I see Shaun Hill I ask him a lot of dumb airplane questions. I asked his dad a lot of dumb questions over the years too. That's just me, I like things that fly.
A dumb mistake by a good pilot can kill a well maintaned plane load of friends.
A good pilot may just save a piece of junk plane from killing me and my friends.
Hopefully a well maintained plane with a well trained pilot leads to a happy plane load of friends.
Most jumpers are more worried about their parachute opening than take off.
That's my thoughts on jump aircraft. What the hell do I know? I'm a helicopter pilot.:P
Now we need Zing and Diverdriver to give their thoughts...

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Using the tail number for the aircraft will only get you the Registration information for that aircraft, (i.e. who owns it, serial number, etc.).
Some aircraft operators will have maintenance info in the aircraft in some form or another. I have seen operators that will make copies of the log book entries and have them in the aircraft.
For aircraft that I was responsable for we had a spread sheet that showed when the last inspection was completed, when the next was due, what the current AD status was. It was signed by an A&P with the mechanics number. We also kept copies of all the 337s, (Major Alterations & repairs) in the aircraft.
We started doing this at the suggestion of our FAA Inspector. It made it easy for them when they did ramp inspections, expecially when the aircraft was away from the home DZ, at a boogie or demo, when the log books were not availlable.
It also let the pilot know the current status of the aircraft.
Check with your pilot. Maybe your DZO does this in some form or another.
If not a hint will not hurt.

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What is the maintenance cycle for a Cessna Caravan Jumpship?



This response is based on requirements in the US. The may not translate to the UK.
There are three different ways that a Caravan can be inspected.
1)100 Hour & Annual
Every 100 hours of operation the aircraft is inspected and then every 12 months. Each time the complete aircraft is inpected.
2)Progressive Inspection as per the maintenance manual. I never used the progressive inspection, so I can not comment.
3)Phase Card Inspection Program.
This program is broken down into 12 Inspections. Every 200 hours you performed one of these inspections. Every 100 hours you would perform a "Mini" Inspection. The Mini was basically checking brakes, tires, prop and filters.
It is difficult to say what is checked at each inspection because it varied from inspection to inspection. But at each 200 hour the prop was always inspected, the engine was always inspected and filters changed and the flight controls were always inspected.
There are also special inspections for the Main Landing Gear, Wing Struts and Spar.
Hope this answered something for you.

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Ask the average skydiver the difference between a puddle of oil under a Beech 18 and the same puddle of oil under a Westwind Beech.



If the average jumper were to ask me this question then I would answer:
If the Beech 18 did not have a puddle of oil under it, then there is no oil in the engine. Radials leak oil, expecially from the exhaust if the have been sitting for awhile.
Where as if there was a puddle of oil under the Westwind Beech I would state that something is wrong because turbines are not suppost to leak.

If you would like I can go more indepth.

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A large problem with jump plane Mx is that there is little to no oversight. And that's where many problems (not all problems) develop. Since people know they won't be watched they might not follow the rules until they feel they need to. Which may not be the same as when the rules say they should. Will more rules make it safer? Depends on the problem and the rule. Someone who ignores the rules now will likely ignore new rules. So, that's where the oversight comes in (or doesn't come in).

By educating jumpers year after year (as there is always a new generation) what to look for and what the history is they become the overseers like it or not. We just have to get them to pay attention. Peer pressure can be a beautiful thing.

What can really burn me is to hear long time skydivers who've been in the sport since the early eighties claim that what they are doing is just fine since that's what they've always done. But that was when the 182s were maybe 20 years old. Now these same 182s are 50 years old and are still being flown hard and long like always. Fatiguing aircraft will become more of a danger in the coming decade I believe. You can only pencil whip or do bear minimum for so long before things begin to fail catastrophicaly.

We need to get DZOs educated on how our fleet is aging and what can be done to counteract those hazards. It's about threat management. First part is to identify and be honest about the threat existing.
Chris Schindler
www.diverdriver.com
ATP/D-19012
FB #4125

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Excellent point !
One MUST look closer and deeper into the structural integrity of the aging fleet. The era of greasing the bearings and changing oil evry 100 hours has long since passed.
It's not the hours accumulated that should dictate what/wnen we perform maintenance in regards to jump aircraft, but rather the CYCLES ........ {starts, take offs and landings} which are considerable in comparison to the averaqge recreational aircraft.
after 50 years of use, stress in the gearbox area, horizontal stab , and main wingspars attachpoints, etc. bear conciderable watching.
We used to spend a couple of weekdays EVERY week looking at all of the fleet to be ready for the weekend. It's amazing what you can find that happens over the course of just one busy weekend to a 182 flying just 9 hours ( up to 20 cyckes or more) Now that the fleet is much older, the things that you find are of a whole different nature.
Still safe. but in need of a little closer attention.
Most of you jumpers know who you are flying with and know what kind of people they are and have a pretty good Idea what shape their equipment is in.
If you don't feel comnfortable, go with your gut ,,,,,,,,, it's kept you alive so far ..............

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By educating jumpers year after year (as there is always a new generation) what to look for and what the history is they become the overseers like it or not. We just have to get them to pay attention.


Thanks Chris for your input.
You are absolutely correct when you state that we need to educate people on this matter.
I know there are people out there that have questions. I've been reading them on the various Incident posts.
I just feel that here is a better place to deal with them then just cluttering up a post with unrelated questions.
I may not have all the answers, but when I do I will state them as fact when possible and if I am using past experiences as speculation then I will explain it as such.

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Runaway, have you ever considered the stress on the Landing Gear of a 182. Not from landings, but from jumpers standing on the step that is attached to th RH Main.
I remember sitting on the deck of the DZ, oh '97ish, having a beer with Lou Sanborne. He mentioned something to me that has always stuck in the back of my mind.
The Landing gear on a Cessna is made of Spring Steel. It is designed to flex upwards on landing as the weigh of the aircraft pushes down.
Now take 4 185-200 lbs skydivers and have them stand on that step in flight. Which way is the direction of the load now.
He told me about when a RH Landing gear broke do to this stress.
It was something I had never thought about. It is something I don't forget when I do an inspection.
Expect the unexpected and you will never be suprised.

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Speaking of 182's. How much of a concern are small cracks throughout the aircraft skin? I have seen on multiple 182's, cracks on the covers that cover where the wings connect to the strut, also have seen alot of cracks on the elevators and such, usually with holes drilled in them to stop the crack from progressing. This always kinda raises the hair on my neck, but there are people who have graduated from aviation programs and such around the DZ and they never seem concerned. These are typically 182's with a 206 engine in them or something much much more powerful than a typical 182 engine. So does th extra engine also warrant concern over extra weight and flying stresses upon the airframe?

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Speaking of 182's. How much of a concern are small cracks throughout the aircraft skin? I have seen on multiple 182's, cracks on the covers that cover where the wings connect to the strut, also have seen alot of cracks on the elevators and such, usually with holes drilled in them to stop the crack from progressing.



The covers where the struts connect to the wings are made of fiberglass. Just being old can make them dry and brittle. Also, they are just that, covers. Or you may here them referred to as fairings. They have nothing to do with the way the struts are connected to the wings.
As for the elevators, I would assume from experience that the cracks you refer to are on the trailing, rear, edge of the elevators or out by the tips.
Wear and tear do age is the most likely cause.
Some newer Cessnas, 1970 & after, have fiberglass tips on the elevators. Same thing as the strut fairings.
Stop drilling a crack is an acceptable repair. The ones on the elevator, though, should have a patch repair.
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So does th extra engine also warrant concern over extra weight and flying stresses upon the airframe? So does th extra engine also warrant concern over extra weight and flying stresses upon the airframe?


The upgrade in engines are fairly new, in respect to the age of most 182s used for jumping. If there are any stress related issue due to the engines they may not be known for some time. It takes time for them to manifest themselves.
As far as the extra weight is concerned this should be factored into the new empty weight of the aircraft if and when a Weight & Balance was done at the engine install. The Max Gross weight remains the same, the usefull load, or how much the aircraft can carry, will be lower.

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The problem is, most jumpers don't even know what color their reserve canopy is, and you want them to debate maintenance schedules?




You bring up a good point. But those are the people who say this is what you should do to keep it safe. People who have no clue about the reg's or what is done behind the scenes with the MX dept. A plane crashes or has an accident and before the flames are even doused out you have some people screaming what should be done before the cause is even known.

Most jumpers dont care anyway. A lot have the attitude "Thats why I have a parachute" attitude. And the proof of that statement is the shit a lot lod of DZ's call an airplane. Some of the places I have been to have abosolute junk for lift that I wouldnt go anywhere near.

Even if the everyday Joe had access to the MX records on a certain jumpship they would have no idea what the hell they were looking at. STC's, AD's, 337's. They would be clueless. When an annual is done a lot of time is spent by the A&P just doing research on what has already been done and what has not been complied with yet in terms of inspections like AD's. So the weekend jumper is not going to spend the time making sure the DZ is up to snuff. In my mind the only thing you can do is trust the DZ is doing what is rewuired to keep the plane airworthy. I know thats not what most want to hear but thats the way it is. Heres a thought. If the plane looks like a total piece of shit, it probably is.
If you find yourself in a fair fight, your tactics suck!

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The problem is, most jumpers don't even know what color their reserve canopy is, and you want them to debate maintenance schedules?




You bring up a good point. But those are the people who say this is what you should do to keep it safe. People who have no clue about the reg's or what is done behind the scenes with the MX dept. A plane crashes or has an accident and before the flames are even doused out you have some people screaming what should be done before the cause is even known.

Most jumpers dont care anyway. A lot have the attitude "Thats why I have a parachute" attitude. And the proof of that statement is the shit a lot lod of DZ's call an airplane. Some of the places I have been to have abosolute junk for lift that I wouldnt go anywhere near.

Even if the everyday Joe had access to the MX records on a certain jumpship they would have no idea what the hell they were looking at. STC's, AD's, 337's. They would be clueless. When an annual is done a lot of time is spent by the A&P just doing research on what has already been done and what has not been complied with yet in terms of inspections like AD's. So the weekend jumper is not going to spend the time making sure the DZ is up to snuff. In my mind the only thing you can do is trust the DZ is doing what is rewuired to keep the plane airworthy. I know thats not what most want to hear but thats the way it is. Heres a thought. If the plane looks like a total piece of shit, it probably is.



What he said. Going over ADs in particular can take hours and hours, and determining which ones are relevant to your particular plane often requires knowing things like the serial number of the propellor hub or what kind of oil pump the engine has installed , etc. (to list just two examples that applied to my Mooney).
...

The only sure way to survive a canopy collision is not to have one.

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Rookie120 & Kallend both have valied points.
With the maintenance records, unless you know what you are looking at, there is noo way to tell if the are bogus or legit.
As far as aircraft apperance, bingo. A good looking aircraft is one that can be fairly assumed to be well maintained.
So lets start there. Using terms and visuals that all jumpers can reckonize.
Walk up to the aircraft when its not flying.
First take a look at the seatbelts. Are any frayed or the color so faded that it does not match. These are no good. Does it buckle easily and release easily. If it does not its no good. Can you read the data tag that every seatbelt half is supposed to have. If you can not read the TSO number on the tag, C22(?), or the tag is missing the seatbelt is no good. If you can not eaisly adjust it, its no good.
On aircraft with a roll-up jump door. Are there screws missing. Are any of the lexan panels cracked or chipped.
In the cockpit, are there missing instruments from the panel. There should be no holes in the instrument panel. If there are put a cover on them.
Are placards falling off or unreadable. Placards are the labels that give info to the pilot. This is no good.
Take a walk around the aircraft. Do you notice screws missing, corrosion, heavy oil stains on the belly, cowlings or nacelles. Are there broken antennas. Are the tires bald.
All these are signs that maybe not enough is being done to the aircraft.

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