BeechTalk - BT - Retractable Landing Gear on High-Wing Cessna

Username Protected · **Posted:** 14 Sep 2017, 16:11

If I remember correctly, my 1981 T210 gear operating speed was top of the green arc (165 kts?) and the gear extended speed was redline (VNE 203 kts?). I not really sure of the numbers, its been at least 10 years.

I never had a problem with 210 gear. It was good off airport and you could use it as a speed brake.

Username Protected · **Posted:** 14 Sep 2017, 16:28

Username Protected wrote:

More recently the 210s have settled down and been fairly "normal". Maybe they are getting rigged better.

Just one thing to remember: Even though they are all "210"s, the gear system in a 1960 210 and a 1980 210 are completely different beasts and are three design generations apart.

All 210 gear systems are not the same.

Robert

Username Protected · **Posted:** 14 Sep 2017, 18:37

Early 210s have engine driven hydraulic pump. Later models have electric hydraulic pump. Both have switches-the week link in both. Having to raise the aircraft almost four feet for the gear to clear the ground was nerve-wracking at best. The special go-no go gage for later models is absurdly expensive. Many mechanics forego this step. Just as any other complicated device, RTFI. At least as often as it takes to understand them.

The 210 is a fine machine- kind of akin to the old Jaguar XKE :duck:

Username Protected · **Posted:** 14 Sep 2017, 19:04

Username Protected wrote:

More recently the 210s have settled down and been fairly "normal". Maybe they are getting rigged better.

Just one thing to remember: Even though they are all "210"s, the gear system in a 1960 210 and a 1980 210 are completely different beasts and are three design generations apart.

All 210 gear systems are not the same.

Robert

Username Protected · **Posted:** 14 Sep 2017, 19:07

Username Protected wrote:

Early 210s have engine driven hydraulic pump. Later models have electric hydraulic pump. Both have switches-the week link in both. Having to raise the aircraft almost four feet for the gear to clear the ground was nerve-wracking at best. The special go-no go gage for later models is absurdly expensive. Many mechanics forego this step. Just as any other complicated device, RTFI. At least as often as it takes to understand them.

The 210 is a fine machine- kind of akin to the old Jaguar XKE :duck:

Im smart enough to avoid defending Cessnas on BT

but just to be accurate my maintenance manual says the mains need to be at least 16" off the floor. :cheers:

Username Protected · **Posted:** 15 Sep 2017, 10:09

Username Protected wrote:

Im smart enough to avoid defending Cessnas on BT

but just to be accurate my maintenance manual says the mains need to be at least 16" off the floor. :cheers:

There's a typo in there somewhere. The graphic shows a minimum of 36".

Username Protected · **Posted:** 15 Sep 2017, 11:26

Mains 16
Airplane 36 in picture.

Is that the same for later models also?

Username Protected · **Posted:** 15 Sep 2017, 11:32

From an insurance standpoint, I can tell you that high wing Cessna's with retractable gear seem to fall off the jacks on a disproportionate basis.

Username Protected · **Posted:** 15 Sep 2017, 14:28

Username Protected wrote:

Mains 16
Airplane 36 in picture.

Is that the same for later models also?

Nobody sets the jacks at the minimum clearance!
I misspoke. Mea culpa. Almost four feet is A tad more than 36"

Username Protected · **Posted:** 15 Sep 2017, 20:00

[quote="Jay Venable"]I cant really compare the two systems as I only have a small amount of time in Bo's but I consider my 210 very stable. The "truck-like" handling that is often mentioned here continues on the ground.

The later models went to a tube gear leg that has a wider stance to put the mains farther back when retracted, which I assume makes them more stable than mine.

After 3 years and 300ish hours the gear on my 1964 210D has been 100% reliable. One of the actuators was barely "sweating" last year so we did new O-rings on both for a total cost of about $5 in parts. The early 210s like mine use an engine driven hydraulic pump, later years went to an electric motor driving the powerpack. As I understand it the emergency pump has a separate stand pipe and is supposed to contain enough fluid to put them down in the event that the engine driven pump fails or is ran dry for some reason.

One nice thing about the system is I am able to swing the gear using just the hand pump which avoids the need for a mule and allows you to stop with them in any position to look at stuff and you can observe them in transit while going as slow as you want.

A quirk that is probably unique to the engine driven pump set up is you really need to monitor the gear while in transit (always a good idea anyways) so as to not let the pump continue running in the event the handle does not automatically go back to neutral. If you allow the pump to keep running in this situation it is possible to burn it up.

While not as simple as the gear on a bonanza I really dont consider it all that complicated. Its essentially just a standard hydraulic ram that actuates a gear to make them pivot. Mine has had the gear doors removed like the later models which simplifies it quite a bit as it removes the hydraulic actuators and sequencing required to open and close the doors. Saves some weight as well at the expense of a few kts. Another nice thing is you can visually check the mains and I have mirrors for nose.

Nice 210, and a GREAT landing :thumbup:

Username Protected · **Posted:** 16 Sep 2017, 00:11

Username Protected wrote:

I cant really compare the two systems as I only have a small amount of time in Bo's but I consider my 210 very stable. The "truck-like" handling that is often mentioned here continues on the ground.

The later models went to a tube gear leg that has a wider stance to put the mains farther back when retracted, which I assume makes them more stable than mine.

After 3 years and 300ish hours the gear on my 1964 210D has been 100% reliable. One of the actuators was barely "sweating" last year so we did new O-rings on both for a total cost of about $5 in parts. The early 210s like mine use an engine driven hydraulic pump, later years went to an electric motor driving the powerpack. As I understand it the emergency pump has a separate stand pipe and is supposed to contain enough fluid to put them down in the event that the engine driven pump fails or is ran dry for some reason.

One nice thing about the system is I am able to swing the gear using just the hand pump which avoids the need for a mule and allows you to stop with them in any position to look at stuff and you can observe them in transit while going as slow as you want.

A quirk that is probably unique to the engine driven pump set up is you really need to monitor the gear while in transit (always a good idea anyways) so as to not let the pump continue running in the event the handle does not automatically go back to neutral. If you allow the pump to keep running in this situation it is possible to burn it up.

While not as simple as the gear on a bonanza I really dont consider it all that complicated. Its essentially just a standard hydraulic ram that actuates a gear to make them pivot. Mine has had the gear doors removed like the later models which simplifies it quite a bit as it removes the hydraulic actuators and sequencing required to open and close the doors. Saves some weight as well at the expense of a few kts. Another nice thing is you can visually check the mains and I have mirrors for nose.

(Retraction at 2:00 and extension at 6:30)
[youtube]https://youtu.be/W1YnCWIX62U[/youtube]

Jay your '64 210D is a great ride... so much bang for the buck. I remember this ship being for sale a few years back. I had inquired about it then.

A very smart engineer-fellow on another forum says the secret ingredient in his 210D is running a 20% mixture of Granville Strut Seal in his power pack... claims he's had no leaks or missing fluid in 20 years, plus the seals stay lubed and in great shape. Not that I would doing such a thing :dancing:

Username Protected · **Posted:** 17 Sep 2017, 03:49

Quote:

The Piper Arrow (PA28), Saratoga and Lance (PA32) and Senecas (PA34) is among the simplest and robust retractable landing gear systems.

I totally disagree, particularly for the Seneca PA-34.

It is a very well known fact that the Piper retract MG trunions were totally under-built, consequently there is a very high incidence of MG failures after hard landings.

The trunions were beefed-up at least a half dozen times over the years, maybe the latest iterations are considered "robust" but the earlier ones certainly were NOT !

Cessna retract gear is about as robust as they come and an extremely hard landing (read crash landing) will result in major structural damage long before the gear fails.

I was right seat in a Cessna 337 "push - pull" when the pilot slammed it on the runway at one of the most notorious airports in the world : Courchevel .

The pilot flared much too high and we basically stalled 12' off the runway but luckily hit MG first. The gear legs flexed sooo much that both brake discs and brake calipers scraped the tarmac. The gear legs then flexed back and bounced us back in the air fot another landing.

Amazingly, the only damage was the brake discs & calipers and bent one of the gear legs.

Username Protected · **Posted:** 17 Sep 2017, 10:13

I have nearly 1000 hours just in 182RGs and have only experienced 2 problems with the gear in that time (3 different N numbers). One was a leak in the fitting at the main gear actuator. Caused the pump to cycle frequently. Pulled the CB in flight and the main gear "sagged" out in trail. Reactivated the system for landing at an alternate airport and then left the gear down for the last 100 miles home.

Second issue was noticing "hydraulic fluid" on the outside of the port leg. Further investigation labeled it brake fluid. Tear up the floor and inspect the saddle, cracked. $16k for a new saddle and $10k for a magnafluxed know good used part. That was on a N number I owned with partners. Ouch. The saddle is what rotates and is driven by the actuator, and the main gear "plugs" into it. The brake line is internal to the gear leg and also mates to the saddle. The saddle is only about 14" long and about 4" in diameter. Much dinero for such a small part...but it is very important!

People take the 182RG into unimproved strips frequently. The robustness of the gear is never a problem, just need to consider adequate floatation with the small tires. The system is pretty simple and with my leaking hydraulic fluid example above, the powered system cannot pump all the fluid overboard. There is enough remaining for manual extension.

Username Protected · **Posted:** 17 Sep 2017, 10:26

Username Protected wrote:

Tear up the floor and inspect the saddle, cracked. $16k for a new saddle and $10k for a magnafluxed know good used part.

Exactly. Not an issue in the Bonanza world. And the nose gear collar as well. One of the guys on the AOPA board was taxiing his 210 and his broke, all he felt was this little rumble so he decided to shut down and have a look. As I recall it took about $20K to fix.

Username Protected · **Posted:** 17 Sep 2017, 10:54

Re: Seneca, the PA-34 are subject to an evolving 100 hour AD for the nose gear which is not pretty. I understand it takes about 8 hours to complete "if the mechanic does it by the book". Many parts in of the nose gear have to be measured to ensure they aren't worn or otherwise damaged or cracked. Nose gear collapses seem to be relatively common, which is probably the reason for the AD. Go figure.

The Cessna retractable main gear is a mixed bag. I will only comment on what I have knowledge of:

1) 172RG main gear pivots are made of aluminium. They can crack. When they crack, the gear doesn't pivot down and you're going in for a belly landing. But it's so rare, right? I bought a 172RG and 6 months later the left main gear pivot failed resulting in a belly landing. Totaled the airplane. Replacement parts from the factory were 15k+ last time I looked. Each side. With no structural improvements over the old ones. There is an aftermarket option but it's not cheap either (plus the cost of repairing the airplane from the belly landing).

I found out a few months later our local flying club had another 172RG pivot fail, and belly landing, about 1 yr before I bought mine. So this is not a rare occurrence.

2) 182RG pivots are mixed. Early models (up to a certain serial number I don't recall offhand) for the first year or so used steel pivots which are considered to be far more robust. After that they were all aluminium pivots as well and subject to the same cracking concerns, although I don't know if it's with the same frequency/regularity.

3) 210 pivots - if anyone actually know about their construction vs 172RG & 182RG I'd be interested to know.