Tie down rings

[65MooneyPilot]

I just noticed in SI-114 that the tie down rings should not be left in for flight. Does everyone take the rings out for flight? I wonder what the logic is for that? 

[Marek7]

I do.  I have forgot once and it did not affect handling at all.  I guess there is a small drag penalty. 

[kpaul]

I leave mine in place.  

You can get these from LASAR and have tie downs and jack points always installed https://lasar.com/product/tie-jack-point-combo/

[larryb]

I leave them in place

[Hank]

I take the tie down rings out of the wings every annual, so that I can jack up the plane. Never flown my Mooney without having all three tie down rings installed, so I can't comment on handling . . . . Almost 11 years now . . .

Edited February 24, 2018 by Hank

[INA201]

I leave in for flight but have considered pulling them off.

[HRM]

1 hour ago, kpaul said:

...from LASAR and have tie downs and jack points always installed https://lasar.com/product/tie-jack-point-combo/

The only way to go. LASAR also has a very clean, 'Buck Rogers' stainless steel tail skid that is also the only way to go. One of the least expensive customizations you can add to an aging Mooney 

[1964-M20E]

I have never taken them out on my E and on my F which has the LASAR rings with built in jack point.

My thoughts why cause excess wear on the threads not great I know.  What could be the reason to remove them?  Falling out and hitting something?? Drag??

 

[RobertGary1]

The poh also says to remove them for flight. 

 

-Robert

[65MooneyPilot]

I do like the SS upgrades. I would think you are just asking for more corrosion problems with them out. 

[RLCarter]

Sometimes the Rings are in, sometimes the Jack Points are in, and sometimes I remember to remove which every I left in. Would be interesting to know Moonys reasoning for wanting them removed before flight. 

[N201MKTurbo]

.05 KTS additional speed? Go Mooney!

Edited February 24, 2018 by N201MKTurbo

[kris_adams]

On 2/23/2018 at 8:33 PM, kpaul said:

I leave mine in place.  

You can get these from LASAR and have tie downs and jack points always installed https://lasar.com/product/tie-jack-point-combo/

Same here.  Left the old rings in, now I leave my LASAR tie downs in all the time even though it's always hangared.

[Mooneymite]

My aircraft is hangared, so the rings are carried in the baggage compartment.

Actually @Hyett6420 there is a 30 KT speed increase with the rings removed, but you have to cover the tie-down ring hole because of the huge low pressure area formed increasing induced drag reducing the increase to only 20 kts.

If you do this, you may have to convert your airspeed indicator to display Mach.

Be careful of the long float on landing.

[Dream to fly]

On ‎2‎/‎23‎/‎2018 at 11:03 PM, RLCarter said:

Sometimes the Rings are in, sometimes the Jack Points are in, and sometimes I remember to remove which every I left in. Would be interesting to know Moonys reasoning for wanting them removed before flight. 

An engineer said so.

[EricJ]

15 minutes ago, Dream to fly said:

An engineer said so.

Or a marketer.   Gotta have that extra knot.

[steingar]

Never heard of this until just now.  I've never seen it in my POH which I've read cover to cover.  I think I'll leave them in. My airplane flies at 160mph indicated at 75% power.  I don't know how  much more I'm going to get out of an O360 in an airplane built in 1962.

[rbridges]

You guys can leave them in, but I'll be the one laughing when I finish the 300nm flight 1.3 seconds faster than you. 

[Hank]

53 minutes ago, rbridges said:

You guys can leave them in, but I'll be the one laughing when I finish the 300nm flight 1.3 seconds faster than you. 

Your fancy cowl will beat mine by a couple of minutes already! So I'm not worried about fractions of a second . . .

[1964-M20E]

11 hours ago, Hyett6420 said:

I removed mine for the huge 20 knot speed increase.  (the fact i still had the tie downs tied to the 180 kg blocks probably didn't help!)  Seriously i did remove mine and it made no difference to the speed whatsoever.  I seem to remember reading on here somewhere that someone noticed that its the things under the wing that cause the drag hence i removed them

As for physical tie downs, here in the UK you tend not to be given nice tight wires to tie down to so I created my own.  Ive attached the PDF of the drawing here, but  each one weighs 180kg which if you add it up means she wont be blown anywhere. Its made of concrete.

You wouldn't have this in American measurements.  We don't unerstand that metric stufffffff.

[Hank]

10 minutes ago, 1964-M20E said:

You wouldn't have this in American measurements.  We don't unerstand that metric stufffffff.

Most places where I've tied down in the eleven years I've owned my Mooney have steel rings buried in the pavement or concreted into the ground. Some have ropes attached; I carry my own ropes for those that don't have any. Seems like one time in South Dakota there was a cable with chains on it, and it was a calm day with the wind gusting only into the high 20s.

I'm sorry to hear that UK airports are plagued with slack cables . . . . . .

[RLCarter]

59 minutes ago, 1964-M20E said:

You wouldn't have this in American measurements.  We don't unerstand that metric stufffffff.

500 = .002699784 Nautical Miles
300 = .000161987 Nautical Miles
72973.39 Inches per Nautical Mile

easy math 

[Hank]

1 hour ago, RLCarter said:

easy math 

As an engineer, I've always defined "easy math" as "up through integral and differential calculus". Differential Equations is where it starts to get complicated. Unit conversion got to be stone simple with my android app "Converter" which conveniently includes Knots.

[RLCarter]

14 minutes ago, Hank said:

As an engineer, I've always defined "easy math" as "up through integral and differential calculus". Differential Equations is where it starts to get complicated. Unit conversion got to be stone simple with my android app "Converter" which conveniently includes Knots.

I use to be good at math, but somewhere between sex, drugs & rock-n-roll the personal computer came out and I have forgotten most of it

[Hank]

Thanks for the explanation, Andrew.

But for the dimensionally challenged, it's 25.4mm = 1 inch, or 304.8 mm = 1 foot. But 25:1 is a decent approximation and works fine in this case. My job works down to the .001", so I'm used to being precise; sometimes my tolerances are only .0005" (half a thousandth).