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Posted

This is not the first thread I have made venting about my maintenance experiences being terrible...   This one has pushed me over the line and I am certain I will be selling both my Mooneys soon as I can... which will unfortunately be another 4 years unless I want to go without an aircraft ( which I do not).  I will be buying an experimental and doing all maintenance myself and for the yearly safety inspection watching/monitoring whatever A&P I have do the inspection.

Here's the story....

Aircraft due for annual... Schedule the aircraft for said annual at a shop, which I have used before and in fact used on the last annual.  I stated that I had some squawks I wanted addressed and disclosed them...  Mostly small items,  a broken zerk fitting, 3 instruments with no backlighting, HSI not receiving ILS signal (arinc 429 bus I think) and the only sort of big item was that my number 5 cylinder runs hot... Now by hot I mean that if I get slow in the climb, the temp might hit 380-385 degrees.  In cruise it will hold at 370-375.  I also noticed that the number 1 cylinder head reads exceptionally cool... around 310 in cruise.  Since I have been round and round with Gami getting the gami spread down below .5 GPH, I wanted the number 1 and 5 CHT sensors swapped to see if it was a sensor issue.   I had recently changed the oil so that was not necessary.  The last item on the list was a pitot static check.

So I drop the airplane off and for the most part, the annual and sensor swap went as expected, but I was told that none of my other squawks were addressed because they just did not have enough time for the annual and those items (they told me it would all take a week). 

My partner test flew the aircraft and now the number 5 cylinder was busting through 395 degrees in the climb and he was not able to get it below 385 in cruise.  AND the airspeed indicator was now reading 20 knots too fast, verified by GPS groundspeed and the G5 airspeed indicator which is still reading properly.    We decided this was unacceptable so the plane went back to the shop and we wanted this investigated/addressed... Both me and my partner went out of our way to leave the aircraft with the shop for another whole week so they could figure out what was going on with the airspeed indicator and investigate the hot cylinder.

Well, the end of the week comes and my partner (who lives by the shop) calls me and tells me that the shop swapped the CHT sensors for 1 and 5 back to where they were, but otherwise did no work on the aircraft.     After another test flight, the airspeed is still 20 knots too high and the number 5 cylinder is still running way hotter than it was previously.

So....  I had an aircraft that was operating quite well... and since the FAA insist on ripping apart the fuel injection system and hooking pressurizing equipment up to my Pitot static system my aircraft is now in worse shape than when I took it in.... and I got to pay for the privilege.

I am so frustrated and I dont know what to do...   I have a lot of flying I need to do soon and the shop is not at my home field...  I am tempted to take the plane to a local avionics shop to have the airspeed issue investigated and send the bill to the shop that handed me back a plane with a fresh cert and an ASI that is 20 knots off.

 

I could take it back to the shop But at this point why would I take it back to them if they let the airplane sit a whole week without touching it?   I am not going to name the shop... they are nice people and are clearly overwhelmed by demand.  I am more upset that the FAA will not budge on the rules for these older aircraft.... I cant touch the fuel system on my mooney, but If I buy a Lancair 4, I can do anything.... It makes no sense... but if that is the game, that is what I will be doing.

 

Posted
7 minutes ago, Austintatious said:

I could take it back to the shop But at this point why would I take it back to them if they let the airplane sit a whole week without touching it?   I am not going to name the shop... they are nice people and are clearly overwhelmed by demand.  I am more upset that the FAA will not budge on the rules for these older aircraft.... I cant touch the fuel system on my mooney, but If I buy a Lancair 4, I can do anything.... It makes no sense... but if that is the game, that is what I will be doing.

My solution was to go to A&P school, which isn't available to some, but maybe more than might think so.    An alternative is to find an A&P that you can work with that will let you do the work and supervise and sign off the outcome.    Either way, you can do essentially all of your own maintenance, but both ways do have some obvious requirements.

  • Like 2
Posted

I’m no expert, but if my cylinder was hotter after they R+R the cowl, I would be looking at baffle seals as a possibility. Might be as simple as that. 
 

does not explain the ASI or or other squawks. 

  • Like 2
Posted

Before you sell and plan to do all your own maintenance, find a shop that will let you help on current annuals.  Then take 3 or 4 days off and do everything you want, and supervise what they do.  It’s really the best of both worlds because you know everything that’s done, yet you don’t have to do anything you don’t want to or don’t have as good of skills for.  But you can personally do everything you want to your specifications.  And you get an appreciation for how long it might take to do 100% yourself.

  • Like 8
Posted

Sounds remotely familiar, I have made the best overall experience going into the shop with the airplane and working with the technician, some work requires multiple test flights, you are the maintenance test pilot by default. I have learnt from every technician that I have ever worked with, passed the A&P written in July and will do oral and practical in September. Still I will keep one Mooney Guru on speed dial and keep an excellent local A&P entertained to help me with stuff I have never done before. The are excellent shops and excellent technicians, the art of the deal is finding them, entertaining them and managing them, covering their weaknesses either yourself or with another technician. There are no bad guys per se, younger guys may need guidance, older guys that are burnt out may just need some cheering up and TLC. Then it is amazing what motivated people can achieve.

  • Like 2
Posted

There are good shops and not so good shops.  And even good shops are facing labor shortages that cause work to run long.

I would start by calling the owner or manager and explain your frustration.  See what they say.  A good shop will stand behind their work and make it right.

If the conversation goes badly, find another shop.  If you post your location, people here can point you to a good shop to try.

Posted

I take my IA to lunch at least every 2 weeks. 

When my boat is in the shop (a large shop at the lake) I order pizza in for the entire shop.

My avionics shop has a woman who runs the front office. It is the owner's mother. She likes Yankee candles. So I make sure I bring one with me every time, usually a seasonal scent.

Make sure they know they are appreciated.

 

  • Like 10
Posted

If you feel competent to maintain a complex experimental aircraft then why can’t you fix all of these issues under the supervision of an A&P?  I’ve fixed a lot of things on my airplane this way. I just ask the shop owner when my plane is going to be pulled in and explain what I want to work on.  I show up and do what I need to get done and have an A&P inspect my work before I leave.   
 

Although we find ourselves in a frustrating situation it’s completely understandable that a shop would prioritize finishing someone’s annual inspection that is preventing them from flying at all versus a squawk that is an annoyance but doesn’t make the plane unairworthy.  
 

The airspeed indicator does sound like a  significant issue caused by the shop. They should fix it but often the person who caused the problem might not be the best person to fix it.  

  • Like 2
Posted

When an airspeed indicator reads higher than normal after an IFR certification, it's usually because the tech goofed when bringing up the airspeed and altimeter with the test box. This results in running the airspeed indicator backwards, and now the needle will rest above zero rather than at or just below zero. The fix involves repair of the ASI. 

  • Like 2
Posted

Maintaining an airplane is a hassle. These things were designed 70 years ago and many are at least 50 years old. As one mechanic once told me, "When they fly, they break. And when they don't fly, they break."

Here's how I do it (and not without some pain ;))

1. I have always done as much supervised maintenance myself as I can. This includes annual inspections. It helps me stay up on the status of everything. 

2. I try to fix every issue as it occurs because I know from experience that each one may involve unforeseen complications and take a lot longer to resolve than expected. I like to focus on one problem at a time.

3. The annual is the annual. The airplane gets inspected and serviced. The only things that get fixed during annual are discrepancies found during the inspection. If discrepancies are not airworthiness items and cannot be fixed expeditiously (perhaps because of parts availability) they get scheduled for a later date.

4. I maintain good relations with several shops. I know which are the best for certain types of problems and take it to the shop best suited to deal with that issue. Not every shop is uniformly good at everything. I also keep up with the maintenance literature from Mooney and Garmin. It's hard for a shop that maintains multiple brands to keep current on them all, and I find that they always appreciate it when I have done the research.

Skip

 

 

  • Like 9
Posted
24 minutes ago, philiplane said:

When an airspeed indicator reads higher than normal after an IFR certification, it's usually because the tech goofed when bringing up the airspeed and altimeter with the test box. This results in running the airspeed indicator backwards, and now the needle will rest above zero rather than at or just below zero. The fix involves repair of the ASI. 

I thought it happens from opening the static system when it is pumped to altitude. This can happen from accidentally knocking the static line off the plane, or opening the alt static or static drain while pumped to altitude. This causes a huge instantaneous step change in pressure. it usually requires an overhaul of the ASI, altimeter and VSI.

  • Like 2
Posted
15 minutes ago, chriscalandro said:

Or the ASI could have been old and worn and it didn’t take well to being pushed beyond what it normally sees in flight.

I think you just get a new ASI and call it done. 

But how is Howard supposed to get his beer money if he isn't fixing instruments? He is the best BTW.

Posted
2 hours ago, chriscalandro said:

Or the ASI could have been old and worn and it didn’t take well to being pushed beyond what it normally sees in flight.

I think you just get a new ASI and call it done. 

 

What do you mean pushed past what it normally sees in flight?   

Why would they have passed the aircraft on the Pitot static test it was 20 knots off during the test that stressed it?

It seems to me like they probably did the test and it passed, then they yanked off the pitot connection before the pressure was down.

Posted
1 hour ago, Austintatious said:

 

What do you mean pushed past what it normally sees in flight?   

Why would they have passed the aircraft on the Pitot static test it was 20 knots off during the test that stressed it?

It seems to me like they probably did the test and it passed, then they yanked off the pitot connection before the pressure was down.

Pitot static test is actually a misnomer. The test is for static system leaks and altimeter accuracy. Unless you ask for it (and they have a fancier test set) they do not test for pitot leaks or airspeed indicator accuracy. 

The static system test set does include a connection to the pitot because you don’t want abnormal differential pressures on the airspeed indicator which can damage it. 

Posted
2 hours ago, PT20J said:

The static system test set does include a connection to the pitot because you don’t want abnormal differential pressures on the airspeed indicator which can damage it. 

Then @Austintatious theory that they may have "yanked off the pitot connection before the pressure was down" is a pretty good one!

Posted
13 minutes ago, MikeOH said:

Then @Austintatious theory that they may have "yanked off the pitot connection before the pressure was down" is a pretty good one!

The reason to connect the pitot during a static test is so the ASI doesn't overspeed, i.e., wrap around past redline, as you take the altimeter up to 20kft or whatever your guy does during the test.    The way this is done is just to connect the pitot to the same pressure the static port sees during the test, so the ASI always reads zero during the test.   Yanking the pitot part of the tester off before the static ports come back up to ground pressure will yank the entire system from altitude back down to ground (because it is just like popping the entire tester system off at once).   The first thing to go will likely be the VSI which might peg past the down limit.

On my tester there's a valve that separates the pitot side from the static side, and two pumps.   If you shut the valve off so that the pitot and static systems are separate, you can use a pressure pump to pump the pitot side up above the static side and do a pitot leak check.   The static side is kept open to ambient pressure during this test.    After that test is done you turn the pressure pump off and bleed down the pitot pressure so the ASI returns to zero.  Yanking the pitot test tube off before the pressure is bled down can definitely damage the ASI.

You can then open the valve that separates the pitot and static sides and turn on the pump that pulls down the pressure (on both sides, since the valve that separates pitot and static ports is open) and the ASI will stay at zero while the VSI indicates climb and the altimeter winds up to the desired altitude. 

If somebody started off with the separating valve closed while pulling down the static pressure the ASI would start winding up and can go past redline pretty quickly if you're not paying attention.   If they then go, "Oops..." and just open the separating valve to fix the mistake, it slams all the air instruments around a bit, particularly the ASI.   Similarly, mine has valves between the system and the two independent pumps to control the rate at which they pressurize or pull down the system, and if you turn either of those the wrong way or too much during operating it can go badly.   There are also "bleed to ambient" valves on each side, that if you turn too fast or the wrong way you can cause problems.

I bought my tester as a derelict off ebay and rehabbed it with new reference instruments, replaced some valves, fixed some leaks, and just generally got it working again.   You can block the test ports and fiddle around with it to get an idea of how to operate it, which I did quite a bit before ever taking it near an airplane.   The number of ways to screw up a test and damage an instrument is very large, and I'm not at all surprised at how often it happens, since failure modes that can damage instruments include not only mishandling or operating the machine, but if a test line pops apart or disconnects somewhere at the wrong moment or falls off the static ports or opening the alt air static port or whatever.

I get the jeebeez a bit whenever I have to do it.    My transponder cert guy, who was also my DME, suggests one way to mitigate risk is to disconnect the static line in the tail and use a threaded fitting to connect to the tester.   This can also be done at the pitot tube with a little more work (and apparently often is with the weirdo pitot-static masts like Pipers, et al, have).   So, yeah, it's a risky operation on a good day, and an inexperienced or marginal operator or marginal equipment or just bad luck can make it worse.

  • Like 4
  • Thanks 2
Posted

Thanks all And EricJ for the input.

I have ordered a slew of things and have spoken with a home base located avionics shop.  I will be sending the airplane in to have to ASI looked at and have a replacement in hand that I will probably have put in anyway since there is a cosmetic issue with the one that is currently in the airplane and reading 20 knots fast... The crummy thing is that this necessitates a re-testing of the pitot system, pretty much the same thing they do for the instrument cert.  So unless I am able to make a case that the ASI was damaged in the first round I will be paying twice for this.

  • Sad 1
Posted

My last two pitot static checks have gone horribly wrong. The first time they just damaged the A/S indicator, it read 40 mph after they got done. I sent it in and had it fixed. Two years later I tried a different shop and they damaged the ASI and the VSI. The ASI was damaged beyond repair and had to be replaced. The VSI They we’re able to repair. They tried to blame it on the age of the indicators and told me that they were not responsible. I took them to small claims court and the day before the court date the owner wrote me a check to settle out of court. I was able to get a pre-flown ASI from a generous mster and it works great. This year it is due so here we go again. I am thinking of taking a video of everything working on the flight over before they start working. I am also thinking about having them verify and signing that the indicators are indicating properly before they start. Don’t know if they will do it but I am over the shops telling me it’s not there fault when you know it is. 

  • Like 1
Posted
1 hour ago, 65MooneyPilot said:

My last two pitot static checks have gone horribly wrong. The first time they just damaged the A/S indicator, it read 40 mph after they got done. I sent it in and had it fixed. Two years later I tried a different shop and they damaged the ASI and the VSI. The ASI was damaged beyond repair and had to be replaced. The VSI They we’re able to repair. They tried to blame it on the age of the indicators and told me that they were not responsible. I took them to small claims court and the day before the court date the owner wrote me a check to settle out of court. I was able to get a pre-flown ASI from a generous mster and it works great. This year it is due so here we go again. I am thinking of taking a video of everything working on the flight over before they start working. I am also thinking about having them verify and signing that the indicators are indicating properly before they start. Don’t know if they will do it but I am over the shops telling me it’s not there fault when you know it is. 

Bad experiences for sure, but you had the right idea after the first shop screwed up your instruments -- find a different shop.  Unfortunately, that's still the right answer.  Go to shop number three, explain what happened at the other shops (no need to name them), show them the video you just took of working instruments.  Not every shop and not every technician is incompetent -- you just have to find the one.

  • Like 1
Posted

Interesting time for owners and mx professionals alike. Demand for maintenance is up, supply seems to be tightening; perhaps due to consolidation, perhaps due to a large number of maintenance professionals retiring.  I’ve often thought about going experimental.  Building an airplane is out of the question right now. Buying a pre owned, amateur built aircraft has all the risks of buying a pre-owned certified aircraft plus the risk associated with the amateur build…and it will still need an IA performed annual.

I really think owner assist maintenance is the most reasonable third way. However, it requires a different type of investment. Humility, patience and personal time are sometimes in short supply among aircraft owners. 

When I first started doing owner assist maintenance, I was basically removing panels and changing tires. After a decade of taking on increasingly complex tasks (fuel tank repairs, mag, starter, generator, engine R&R etc), I can honestly say no one knows my airplane as well as I do. Almost no dispatch issues in the last decade.
Monetarily, owner assist maintenance has cost me pennies on the dollar by aviation standards, but it’s taken years of investing in relationships to get here.

 

 

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