Jacking up the Ranger

[AmigOne]

I don't think that there is any documented damage on short body - or long body since J & K models are included in this SB - due to this so called improper jacking or else the FAA might have issued and AD on the subject. And even then we have several cases of type associations (Beechcraft, Mooney, Cessna) going after the FAA and have them rescind ADs which had been been issued prematurely and w/o adequate engineering justification. I'm still waiting somebody to comment as to why on the same SB Mooney recommends to remove the tiedown rings before flight.

[carusoam]

I had a bent eye-bolt that the '65C came with. My concern would be thread damage or other unheard of, easy to goof up challenge, and drop the plane on it's nose situation.

But then I also hope my mechanic is good enough to know the difference and his boss has the insurance to cover the loss...

Best regards,

-a-

[Sabremech]

Here's how I jack a 66 M20C. I've done a mod to my doghouse by adding an access panel to get to the engine lift point. Much easier to do and done IAW Mooney service instructions.

David

 

[carusoam]

Very nice David.

It took me years of ownership to even know that hardware was in there...

It's hard to remember things you only see at annual.

I take more pictures now...

Best regards,

-a-

[Bob_Belville]

This is what we do. The weight is substantial and the connections are secure. 

[1964-M20E]

Sabermech

Looking at your jacks they appear to be homemade. How do you mechanically lock the plane once jacked or do you rely on the hydraulics?

I’ve been contemplating building a set but my only stopping point is the mechanical locks. I have looked at many and had many ideas only thing holding me back is dedicating the time to build them.

FWIW My MX uses a tail stand.

[N601RX]

Here are the ones I built a couple of years ago.  I used split steel locking collars  from Mcmaster and machined them out to fit the jack shaft. I did some test here at work in one of our presses that has instrumentation on it and when tightened down it took over 4,000 lbs before they began to move.

 

The only time I use the Collars is if it is going to be left up for a extended period of time.

[Sabremech]

Hi Bob,

I built a tail stand much like you have until I found out about Mooney service instructions M20-114. I no longer use the tail stand.

 

 Hi John,

 I rely solely on the hydraulics with my jacks. I do not leave the airplane overnight or an extended period of time on the jacks, just in case. I've never had one fail yet and I'm not going to safety myself out of maintenance or flying.

 

 David

[1964-M20E]

Here are the ones I built a couple of years ago.  I used split steel locking collars  from Mcmaster and machined them out to fit the jack shaft. I did some test here at work in one of our presses that has instrumentation on it and when tightened down it took over 4,000 lbs before they began to move.

 

The only time I use the Collars is if it is going to be left up for a extended period of time.

Thanks

HOT fast and cheap I like that. I did not think about welding directly to the cylidner for the stablizers.

[N601RX]

Weld fast and then cool.  I was able to do it quickly without overheating the cylinder.  The 4 leveling bolts are also a nice feature to have.

[Bob_Belville]

Paint 'em.

[carusoam]

Is there a rule or guidance for all the hardware that gets tossed on the tail stands???

The stand that is resident in the MX shop at home is full up with unidentified treasure/trash. I would hate to be forced into having to use any of it???

Best regards,

-a-

[scottfromiowa]

That is Tonto's job..

[fantom]

That wasn't nice, Bob

 

A recent thread on Mooneyspace about jacking a Ranger resulting in a discussion of Mooney service instructions M20-114 from 2008 which states that Mooney no longer recommends holding down the tail any of the short and medium body models when jacking the plane. Instead the top cowl should be removed and the front of the plane lifted using the engine eye bolt.

Most of the posters were not aware of the MSI and were puzzled as to the reason that what has been SOP for decades is not a good idea.

Anyone here have the skinny? Was there an incident?

Thanks,

Bob Belville

N943RW, '66 M20E
 

[mike28w]

  Interesting topic.......  This was discussed a few years ago.  If memory serves, there have been 3 different suggestions from Mooney.

  1.  restrain the tail

  2.  some sort of cradle under the prop

  3. engine hoist to lift the engine

 

  Does it seem like Mooney is either "winging it"  or is just following the latest CYA suggestion..??  My take on this ( and I hold no credentials at all) is that whatever you do, you should do it gently. 

 

  As always , common sense should rule the day ....raise the airplane slowly,  evenly and gently , don't go jumping/bouncing around on the plane when it is on jacks, lower the plane slowly, evenly and gently...  My uneducated opinion is that if you're careful, any of the above methods will probably work.....And if you're not careful , you can probably break the plane with any of these methods....

 

  just my 2 cents.....mike

[fantom]

   just my 2 cents.....mike

 

Your 2 cents is spot on, Mike, and as good 'skinny' as can be had, even over at that other place.

 

Much ado about nothing, IMHO. There are more important things to concern ourselves with, as I learn anew on this forum all the time.

[Bob_Belville]

Good as can be had? It remains a puzzle to me that a definitive reason WHY Mooney changed their instruction has not appeared. A lot of speculation, much of it logical enough, but at this point we still have an IA insisting the only right, factory approved, procedure is to use the engine bolt while as I read the posts, most others will continue to use the tail tie down.

 

I use the tail myself, I provided a pic of our weighted tube, so I would still be very interested to understand what caused Mooney to change their procedure. My instinct to to assume I'm missing something. If someone KNOWS and has shared that information I have missed it.

 

Caution: this is a discussion list. Almost anyone can post almost anything. Present company not excepted. The reader should carefully consider this before depending upon advice that might result in action causing risk to plane or pilot.

 

Shalom

[Sabremech]

While I can only offer my thoughts as to why Mooney changed the procedure, the correct way to jack your airplane if applicable by model to Mooney SI M20-114 is with jacks and an engine hoist not a tail stand. As an A&P/IA, if I condoned or recommended any other method, I'd be recommending violating the FAR's.

 

 

 I know that this sounds silly and it probably is as I use to jack my airplane with a tail stand too, but when new procedures come out, we're obliged to follow them.

 

 David

[Bob_Belville]

David, I understand your position completely. Which is why I had hoped to get someone with factory authority to comment on the MAPAlist which they monitor. It seems odd that no one has been able to speak with authority about the context of the change. Oh well. The china store rule probably applies -- you breaks it you owns it.

[N601RX]

Perhaps the more interesting point to your post on the MAPA list is that with the best MSC's and factory personnel monitoring it no one screamed don't do it, or if they did, I missed their post.

[Sabremech]

Let me throw these questions out there. Who is liable for the airplane if something were to happen and the correct procedure is not used? Who's liable if the owner insists it's ok to jack the airplane using a tail stand and something happens? Is it really worth it to not follow current tech data?

David

[AmigOne]

"Is it really worth it to not follow current tech data?"

If "data" are values of qualitative or quantitative variables, Mooney in its SB did not provide any "data", much less a justification of any sort for the SB. If they had we wouldn't be having this conversation. As stated before there is no record of an inflight or any other tail failure that can be attributed to the way in which the airplane has been lifted in the past. On the other hand if 40 years of improper handling of the airplane could have weakened the structure then a mandatory inspection (AD) of the tail should have been issued.

I assume also that nobody knows why the same SB indicates that the tiedown rings be removed before flight? Perhaps some of our A&P/IA friends can venture an opinion on this item because I am really curious.

As far as I am concerned, I did not do it and will not do it again.

[Bob_Belville]

David, do you suppose Mooney would have any responsibility if a plane was damaged or someone was hurt using the engine bolt? I know we are litigious but I'd think that the factory is out of the picture based on many thousands of operations using the tail tie down.

 

Re the removal of the wing tie down bolts, Before the new tie down/jack point combo mod, the wing tie down ring had to be removed and replaced with jack bearing points to jack the plane. The original "Owners Manual" for my '66E describes these parts calling the rings "removable" but does not require removal for flight. I seem to recall that there were occasions when rings fell off, perhaps when the pilot/mechanic did not fully tighten in order to line the ring parallel to the fuselage to minimize drag. I know that sounds silly but we are speed fanatics.    

[N601RX]

If the tiedown points are left in and not tightened down completely, they will eventually wear the threads away from vibration.  I had this happen to one of mine, I have no idea how many hundreds or thousands of hrs it took for this to happen.  It appeared the previous owner left them in all the time.

[Sabremech]

Is it really that hard to understand Mooney Service INSTRUCTIONS M20-114 and what instructions it calls out? Whether you believe that mooney provided qualitative or quantitative variables doesn't detract from the fact that they changed the procedures for us in maintaining our older Mooney's. I'm  baffeld by the resistance here to a fairly new procedure and the demand that Mooney justify it. Really? I'm glad Mooney did this and that it's not an AD or other actions deemed necessary by the FAA versus the manufacturer.

 

 Hi Bob,

 I believe Mooney is out of the picture since they released SI M20-114. It now falls to the owner / A&P/IA who is maintaining the airplane. I know that if an owner told me to use a tail tie down to jack his aircraft, I'd have to politely refuse and show him the SI issued by Mooney and explain that is how it needs to be done from now on. It really doesn't matter that it's been done for the last 40 years now because as an A&P I'm bound to follow the current instructions (data).

 

 

 I'll venture to answer the tie down question as one of there being the possibility for corrosion to set up in the threads of the tie down ring / jacking fittings. Also, to possibly prevent someone from using the tie down rings for jacking, potentially resulting in them breaking and damaging the aircraft.

 David