Manual Gear Speeds

[macosxuser]

I'm curious, the gear speed on my Johnson Bar '66E is 120mph. Of course, as soon as I'm off the runway, the gear is coming up. The part I don't understand is why the slow speed for extension? How is the later electric J models different to allow the faster extension speed, except for the gearing of the motor? The motor should be irrelevant for the manual gear, but the rest is the same? Doors, weldments, all of it?

Basically, why to I have to pull my power darn near to idle for 2-3 miles to get the gear down, and how the hell can I do real instrument work in a busy environment with these restrictions without killing my 25smoh IO-360.

Input is appreciated.

[gsxrpilot]

I certainly wouldn't worry about "shock cooling" your engine. That really isn't a concern with the small engines. My best reference for that comes from the guys at the Advanced Pilot Seminar.

I don't really know the exact purpose for the fairly low airspeed limit but I suspect it has something to do with being able to control the Johnson Bar at higher airspeeds. You can test this by taking off and waiting until over 100 mph to raise the gear. It's almost impossible to control the Johnson Bar with your hand at that speed.

I'm not an A&P but did about 400 hours in a manual gear M20C with lots of IFR time.

[carusoam]

Wait until you release the gear in flight..!

The J-bar rips through the cabin at a high rate of speed and whacks the instrument panel pretty hard.

Makes for a long lasting memory anyway.

There is probably stress limits on all the things that are attached to the system, from the gear doors to all the nuts and bolts...

Before MS, learning about the nuances of these systems was often done using trial and error.

MS is so much better.  

Best regards,

-a-

[MyNameIsNobody]

The 120 is gear EXTENSION Not retraction.  You have to slow the plane to 120 before extending the gear.  You are NOT retracting gear at 120.  Too much resistance.

[rbridges]

I don't think my plane will do much over 120 with gear down. There is a guy at my airport that dropped the gear in his ovation at speed and it bent the doors to the point where they had to be replaced. 

[cctsurf]

11 hours ago, rbridges said:

I don't think my plane will do much over 120 with gear down. There is a guy at my airport that dropped the gear in his ovation at speed and it bent the doors to the point where they had to be replaced. 

That ^^^^^.  Your gear doors won't handle the speeds.

[Ned Gravel]

On 2016-11-08 at 10:35 PM, rbridges said:

I don't think my plane will do much over 120 with gear down.....

It is actually 138 mph in an E model.   Don't ask me how I know this.....

[rbridges]

7 hours ago, Ned Gravel said:

It is actually 138 mph in an E model.   Don't ask me how I know this.....

Let he who hasn't forgotten to raise his gear or flaps cast the first stone....

[1964-M20E]

1 hour ago, rbridges said:

Let he who hasn't forgotten to raise his gear or flaps cast the first stone....

Let's not forget on the 64 and earlier models with the manual retractable step. that will cost you about 5.

 

 

[macosxuser]

Ok, trial and error aside. My gear comes UP at 80 or slower, that is not a factor.

BUT in level flight, I have to be at <15"mp for 2-3miles to get to 120mph, and it's impossible to get there in 500fpm descent at all even at idle. The gear doors and everything associated with them are good to 140mph as indicated by the later J models. I have no trouble controlling the Johnson bar AT 120mph, is there anything else I'm missing?

I AM an A&P, and a CFI, but I'm just trying to figure out why what is OK for a J is not OK for an E. Obviously the Ovation dropping the gear above the rating operating speed is a bad idea. OK, that we understand. The Ovation has three sets of numbers posted though, VLe 164KIAS (Speed where the landing gear may be left extended without damage). VLo Retraction 106KIAS (Landing gear operation speed in retraction cycle). VLo Extention 140KIAS (Landing gear operation speed in extension cycle).

These equate to MPH like so:

VLe 188 MPH (Above my VNE)

VLo (Retraction) 122mph, almost a dead ringer for my E's VLo

VLo (Extention) 161mph.

 

Now anyone who has flown an Johnson bar knows you don't let it get fast on retraction. Above 90mph, it's really tough to strong arm it up. I have personally never had trouble keeping it controlled going down though. I guess my question is, has anyone attempted to get a faster EXTENSION speed approved to make the airplane more friendly in IFR operations? This is especially relevant to me in Socal, where almost everything the controllers want you to do is slam-dunk style approaches. A gear EXTENSION speed of 130-140MPH would go a long way into not wanting $4k worth of speedbrakes. I really want to do some basic speed mods to mine, but anything that makes it slicker at this point is a negative to me in the approach phase.

Also, shock cooling is not a myth. I'm all about being easy on the equipment, and gear doors are cheaper than major overhauls.

[carusoam]

Best worded question of the evening, mac.

The challenges I see are finance vs. function.

Looking at function...

1) The speedbrakes are very effective devices that can be deployed at incredibly high speeds.  They are tiny in size, but generate a large amount of drag by altering the AOA needed to maintain flight.

2) The gear work nicely because they are a huge amount of parasite drag.

3) To improve the strength of the gear, it would probably require every related nut, bolt, control rod and piece of sheet metal to increase one size.  Then add the required testing and documentation.

4) When you are done creating the stronger system, you are still bound by the safety issues of deploying at too high of a speed.  Part of this depends on the skill and strength of the pilot.

 

When it comes to costs,

5) compare what it costs to adapt a higher speed set of landing gear from another Mooney.  That isn't low cost either.

6) In the case of the Long Bodies, The L was weight limited by it's landing gear.  The Bravo was LBII, refined...  Yet, nobody got the documents together to put the Bravo gear on an L.

7) Spreading the cost of the STC amongst your closest Mooney friends would require enough people to want to have this ability.

8) The slam dunk approach isn't very common to most Mooney pilots.  Find a thread that covers speed brakes.  Get ready for a discussion on efficiency v. Good piloting, etc...

9) operating outside the known speed limits is tough on the equipment and not recommended...

10) installing Speed brakes is low cost and available today compared to the other methods.

11) know that if there was extra strength in the system, it comes at a cost of weight.  Mooney spent decades removing all the excess weight, leaving nothing but speed limited strengths and limitations.

 

Let me know if I missed something.  These are PP ideas, not a mechanic or CFI....

Best regards,

-a-

[Pictreed]

I haven't had a problem on approaches.  I usually slow just before FAF. However, I haven't been slam dunked by ATC yet.  Mac, is that when you're having the problem?

 

[TheTurtle]

due to the slipperyness Ive been dropping a little below glideslope and pulling the nose up to get gear speed on the glideslope.  Its a dance for sure.  I concur 140 would be nice. 

[rbridges]

yep.  I usually have to nose up and gain a little altitude to slow down enough for gear extension.  I thought I had asked the same question before--if there were any changes that resulted in higher gear extension speeds in later models--but I don't recall getting a solid answer.

[Hank]

It's probably related to stress on the actuator (your right arm) and the force that high speed extension places on it. To say nothing of how fast that big chrome stick would swing through the middle of the cockpit . . .

There were structural changes inside the wing that raised flap speed. Don't know if anything similar happened to the gear, other than sawing off the big chrome bar and installing an electric motor.

[macosxuser]

On 11/14/2016 at 8:18 PM, Hank said:

It's probably related to stress on the actuator (your right arm) and the force that high speed extension places on it. To say nothing of how fast that big chrome stick would swing through the middle of the cockpit . . .

There were structural changes inside the wing that raised flap speed. Don't know if anything similar happened to the gear, other than sawing off the big chrome bar and installing an electric motor.

And this is what I'm getting at. From everything I've seen, there is NOTHING different about the E to the J except the actual mechanical actuator itself. The system does not need to be modified, the gear doors do not need to be changed, nothing. I would even venture a guess that the Ovation and up 160mph gear speeds would work in a J if the motor and trans was changed to match, but that is just speculation, as I have never had anything newer than a 80's 252 in for annual. $4k for speed brakes, or a 337 to add VLO (Extension) and VLE speeds to the airplane...? Seems like it might be worth the paperwork exercise.

[Jerry 5TJ]

1 minute ago, macosxuser said:

And this is what I'm getting at. From everything I've seen, there is NOTHING different about the E to the J except the actual mechanical actuator itself.

Well, the J does have inner gear doors, unlike stock pre-J models.  Doesn't answer your question.  I just accepted 120 mph as gospel.  

Agree (based on 1300 hours in E model) that you have to plan ahead in IFR operations.  My tactic was to get down to 18" MP at about 1" per minute, then on ILS as the GS came alive to pull up a bit to 120 mph & drop 'em.  Not elegant, but usually effective.  

In SoCal I usually flew the approaches at 140 mph anyway and dropped the gear on short final. I can tell you from experience that if I dropped the gear at GS intercept on the ILS19R at KSNA I did not become the controller's new BFF.  Ditto for the pilot flying the 737 in trail.  

[TheTurtle]

4 hours ago, Jerry 5TJ said:

Well, the J does have inner gear doors, unlike stock pre-J models.  Doesn't answer your question.  I just accepted 120 mph as gospel.  

Agree (based on 1300 hours in E model) that you have to plan ahead in IFR operations.  My tactic was to get down to 18" MP at about 1" per minute, then on ILS as the GS came alive to pull up a bit to 120 mph & drop 'em.  Not elegant, but usually effective.  

In SoCal I usually flew the approaches at 140 mph anyway and dropped the gear on short final. I can tell you from experience that if I dropped the gear at GS intercept on the ILS19R at KSNA I did not become the controller's new BFF.  Ditto for the pilot flying the 737 in trail.  

been awhile since youve been here ehh?  Its 20R now!!

[geoffb]

If you're not below gear speed at glideslope capture, you need a new instructor.  You shouldn't have any trouble being below 120 after completing procedure turn inbound.  Drop the gear at intercept and you're at 3 degrees decent.

[cctsurf]

1 hour ago, geoffb said:

If you're not below gear speed at glideslope capture, you need a new instructor.  You shouldn't have any trouble being below 120 after completing procedure turn inbound.  Drop the gear at intercept and you're at 3 degrees decent.

The problem is not the lack of ability to fly under 120 after the procedure turn, the problem is the traffic behind and the controller doesn't want an airplane flying a pokey 120mph.  You become persona non grata very quickly (ha...ha).

[geoffb]

Understand.  Not to derail too far, but what if you were shooting the approach in a 152?  It's up to the controllers to sequence it, correct?  Back to the topic.  Are we sure that the gear doors, gear door links, gear legs and gear trunnion bearings are the same from 1966 to later models?  There's a lot of parts in the system that see a lot of load with the gear out of the wells.  We know that the stub spar on the old planes take a beating from exceeding flap speed.

[Mooneymite]

13 hours ago, geoffb said:

If you're not below gear speed at glideslope capture, you need a new instructor.

Hmmmmm.  I don't know that I agree with this.  In some cases ATC vectors us to intercept final quite a ways out-side the marker.well above marker alititude...particuarly at busier airports.  Do you really want the gear down 10 miles outside the marker, or do you want to stay clean and ride the slope at above gear speed for awhile?  While this can be challenging in the lowly C without speed brakes, it can be done as long as you're not unduly afraid of the "dreaded shock cooling".

[Hank]

On my Instrument checkride, shooting the ILS into a Class C, there I was at 90 knots, Takeoff flaps and Gear down, putting down the glideslope when a Lear checked in behind me and was advised to "reduce speed 50 knots" due to traffic making 80 knots [Hey! That's me!]. I asked the DPE if I should be nice and speed up, he said "sure, let's see what you can do." So I cleaned up and my lowly C without speed brakes came down the glideslope at 130 mph until 3nm out, when I reduced power, eased in a little Up yoke, then when the ASI looked good added Takeoff Flaps then Gear Down for a nice touch and go, and took the Miss out to the VOR for a nice hold. Granted, there was additional yoke work and some trimming, but it wasn't anything major, and I didn't get more than a dot off of the glideslope.

You got to have things in your Bag of Tricks . . . it makes life much nicer.

[Mooneymite]

Just now, Hank said:

You got to have things in your Bag of Tricks . . . it makes life much nicer.

Absolutely.

[Ned Gravel]

6 hours ago, Hank said:

On my Instrument checkride, shooting the ILS into a Class C, there I was at 90 knots, Takeoff flaps and Gear down, putting down the glideslope when a Lear checked in behind me and was advised to "reduce speed 50 knots" due to traffic making 80 knots [Hey! That's me!]. I asked the DPE if I should be nice and speed up, he said "sure, let's see what you can do." So I cleaned up and my lowly C without speed brakes came down the glideslope at 130 mph until 3nm out, when I reduced power, eased in a little Up yoke, then when the ASI looked good added Takeoff Flaps then Gear Down for a nice touch and go, and took the Miss out to the VOR for a nice hold. Granted, there was additional yoke work and some trimming, but it wasn't anything major, and I didn't get more than a dot off of the glideslope.

You got to have things in your Bag of Tricks . . . it makes life much nicer.

I do this all the time.  There have been times when places like Philly want you to fit into the commercial traffic for DHC 8s and CRJs.  Keeping the speed up until shortly before crossing the fence, and then slowing it all down while staying on G/S is part of fitting into their system - and doing it safely.  My E model will do that and dropping the manual gear above 120 mph is no biggie.  

Mind you, all that is really only possible if the approach is visual from 5 miles out.  If IMC to minima, I will not do that.  In that type of situation, the Lear behind me can wait because my Mooney will be configured for TOGA from at least 1500' above TDE and my approach speed is in the white arc at 90 mph.

In the 11 years I have owned it, Clarence has yet to find a bent gear door.