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nick(at)container.com
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 Posted: Wed Feb 08, 2012 9:15 am Post subject: Lost Hydraulic pressure in flight |
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Dear Commander Gurus’ :
We started to lose hydraulic pressure in my 690A commander .Pressure went from 900# to 500# . We followed emergency procedure which calls for the pulling of the breaker for the aux. hydraulic pump and continued the flight .Then as is procedure we pushed in the breaker and the gear came down without a problem..
My question is why not fly with the aux. hydraulic breaker pulled all the time? This would prevent loss of all fluid if you did not catch the loss soon enough…
Any comments ? Nick N674NM
From: owner-commander-list-server(at)matronics.com [mailto:owner-commander-list-server(at)matronics.com] On Behalf Of Barry Collman
Sent: Wednesday, February 08, 2012 4:08 AM
To: commander-list(at)matronics.com
Subject: RE: SALVAGE OR DERALICT COMMANDER
Hi Moe,
Last I knew:
N55GL, 680F(P) s/n 1200-104, was derelict at Berry Hill, Georgia. Info from a photo taken in January 2011.
N27GA, 680F(P) s/n 1212-111, was derelict at Corona, California. Info from a photo taken in February 2011.
N70QT, 680F(P) s/n 1208-109, was being parted out by Mountain Air LLC., Marion, Iowa following its accident in July 2009.
If none of these prove fruitful, I’ll try some of the other Models.
Very Best Regards,
Barry
From: owner-commander-list-server(at)matronics.com [mailto:owner-commander-list-server(at)matronics.com] On Behalf Of Moe Mills
Sent: 08 February 2012 07:03
To: Com
Subject: SALVAGE OR DERALICT COMMANDER
COMMANDERLAND'
DOES ANYONE KNOW OF A
680t
680flp
680F(p)
THAT IS EITHER DERALICT OR BEING PARTED OUT?
THANX!
Moe Mills
N680RR
680F(p)
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n55bz(at)cox.net
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| Posted: Wed Feb 08, 2012 9:37 am Post subject: Lost Hydraulic pressure in flight |
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This is the procedure which has been strongly advocated by our high priest, Gordon, for years. It sure makes life simple in the event of a hydraulic problem.
Kindest regards,
Bill
On Feb 8, 2012, at 11:10, <nick(at)container.com> wrote:
[quote] Dear Commander Gurus’ :
We started to lose hydraulic pressure in my 690A commander .Pressure went from 900# to 500# . We followed emergency procedure which calls for the pulling of the breaker for the aux. hydraulic pump and continued the flight .Then as is procedure we pushed in the breaker and the gear came down without a problem..
My question is why not fly with the aux. hydraulic breaker pulled all the time? This would prevent loss of all fluid if you did not catch the loss soon enough…
Any comments ? Nick N674NM
From: owner-commander-list-server(at)matronics.com [mailto:owner-commander-list-server(at)matronics.com] On Behalf Of Barry Collman
Sent: Wednesday, February 08, 2012 4:08 AM
To: commander-list(at)matronics.com
Subject: RE: SALVAGE OR DERALICT COMMANDER
Hi Moe,
Last I knew:
N55GL, 680F(P) s/n 1200-104, was derelict at Berry Hill, Georgia. Info from a photo taken in January 2011.
N27GA, 680F(P) s/n 1212-111, was derelict at Corona, California. Info from a photo taken in February 2011.
N70QT, 680F(P) s/n 1208-109, was being parted out by Mountain Air LLC., Marion, Iowa following its accident in July 2009.
If none of these prove fruitful, I’ll try some of the other Models
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John Vormbaum
Joined: 21 Aug 2006
Posts: 273
Location: SF Bay Area, CA
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| Posted: Wed Feb 08, 2012 9:43 am Post subject: Lost Hydraulic pressure in flight |
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Nick, I was trained on my 500B to “rotate, gear up, flaps up, pull aux breaker”. Most of the piston guys were trained the same, from what I know. I think it’s a good way to fly.
I also speak from the ‘other side’ having had a complete hydraulic failure that resulted in a very gentle nosegear collapse about 7 years ago. That was really from my own stupidity, having regained some hydraulic pressure after the failure, and thinking I could cycle the gear. I broke the cardinal rule: DON’T TOUCH THE GEAR HANDLE once you’ve put it down.
Also, guessing that there is some system commonality between my 500B and your 690A, it would be worth pointing out (IIRC) that the aux pump only operates the flaps, brakes and steering. 500# from the aux either isn’t enough oomf or enough volume to run the gear and I think it’s not in the same circuit. I could be wrong on this but I don’t think so.
On the bright side, even if you have zero hydraulic pressure, the gear will come down and lock by just putting the gear handle down.
Cheers,
/J
From: owner-commander-list-server(at)matronics.com [mailto:owner-commander-list-server(at)matronics.com] On Behalf Of nick(at)container.com
Sent: Wednesday, February 08, 2012 9:10 AM
To: commander-list(at)matronics.com
Subject: Lost Hydraulic pressure in flight
Dear Commander Gurus’ :
We started to lose hydraulic pressure in my 690A commander .Pressure went from 900# to 500# . We followed emergency procedure which calls for the pulling of the breaker for the aux. hydraulic pump and continued the flight .Then as is procedure we pushed in the breaker and the gear came down without a problem..
My question is why not fly with the aux. hydraulic breaker pulled all the time? This would prevent loss of all fluid if you did not catch the loss soon enough…
Any comments ? Nick N674NM
From: owner-commander-list-server(at)matronics.com [mailto:owner-commander-list-server(at)matronics.com] On Behalf Of Barry Collman
Sent: Wednesday, February 08, 2012 4:08 AM
To: commander-list(at)matronics.com
Subject: RE: SALVAGE OR DERALICT COMMANDER
Hi Moe,
Last I knew:
N55GL, 680F(P) s/n 1200-104, was derelict at Berry Hill, Georgia. Info from a photo taken in January 2011.
N27GA, 680F(P) s/n 1212-111, was derelict at Corona, California. Info from a photo taken in February 2011.
N70QT, 680F(P) s/n 1208-109, was being parted out by Mountain Air LLC., Marion, Iowa following its accident in July 2009.
If none of these prove fruitful, I’ll try some of the other Models.
Very Best Regards,
Barry
From: owner-commander-list-server(at)matronics.com [mailto:owner-commander-list-server(at)matronics.com] On Behalf Of Moe Mills
Sent: 08 February 2012 07:03
To: Com
Subject: SALVAGE OR DERALICT COMMANDER
COMMANDERLAND'
DOES ANYONE KNOW OF A
680t
680flp
680F(p)
THAT IS EITHER DERALICT OR BEING PARTED OUT?
THANX!
Moe Mills
N680RR
680F(p)
| Quote: | | http://www.matronics.com/Navigator?Commander-List http://forums.matronics.com http://www.matronics.com/contribution |
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nick(at)container.com
Guest
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| Posted: Wed Feb 08, 2012 10:48 am Post subject: Lost Hydraulic pressure in flight |
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John,
When I pushed in the aux hyd breaker the pressure went back up to 900# ..maybe residual hyd fluid flowed back in the tank ? …I also had pulled the breaker for the gear thinking it might help stop the flow from the unknown location . Later we found that O rings were leaking..nick
From: owner-commander-list-server(at)matronics.com [mailto:owner-commander-list-server(at)matronics.com] On Behalf Of John Vormbaum
Sent: Wednesday, February 08, 2012 9:38 AM
To: commander-list(at)matronics.com
Subject: RE: Lost Hydraulic pressure in flight
Nick, I was trained on my 500B to “rotate, gear up, flaps up, pull aux breaker”. Most of the piston guys were trained the same, from what I know. I think it’s a good way to fly.
I also speak from the ‘other side’ having had a complete hydraulic failure that resulted in a very gentle nosegear collapse about 7 years ago. That was really from my own stupidity, having regained some hydraulic pressure after the failure, and thinking I could cycle the gear. I broke the cardinal rule: DON’T TOUCH THE GEAR HANDLE once you’ve put it down.
Also, guessing that there is some system commonality between my 500B and your 690A, it would be worth pointing out (IIRC) that the aux pump only operates the flaps, brakes and steering. 500# from the aux either isn’t enough oomf or enough volume to run the gear and I think it’s not in the same circuit. I could be wrong on this but I don’t think so.
On the bright side, even if you have zero hydraulic pressure, the gear will come down and lock by just putting the gear handle down.
Cheers,
/J
From: owner-commander-list-server(at)matronics.com [mailto:owner-commander-list-server(at)matronics.com] On Behalf Of nick(at)container.com
Sent: Wednesday, February 08, 2012 9:10 AM
To: commander-list(at)matronics.com
Subject: Lost Hydraulic pressure in flight
Dear Commander Gurus’ :
We started to lose hydraulic pressure in my 690A commander .Pressure went from 900# to 500# . We followed emergency procedure which calls for the pulling of the breaker for the aux. hydraulic pump and continued the flight .Then as is procedure we pushed in the breaker and the gear came down without a problem..
My question is why not fly with the aux. hydraulic breaker pulled all the time? This would prevent loss of all fluid if you did not catch the loss soon enough…
Any comments ? Nick N674NM
From: owner-commander-list-server(at)matronics.com [mailto:owner-commander-list-server(at)matronics.com] On Behalf Of Barry Collman
Sent: Wednesday, February 08, 2012 4:08 AM
To: commander-list(at)matronics.com
Subject: RE: SALVAGE OR DERALICT COMMANDER
Hi Moe,
Last I knew:
N55GL, 680F(P) s/n 1200-104, was derelict at Berry Hill, Georgia. Info from a photo taken in January 2011.
N27GA, 680F(P) s/n 1212-111, was derelict at Corona, California. Info from a photo taken in February 2011.
N70QT, 680F(P) s/n 1208-109, was being parted out by Mountain Air LLC., Marion, Iowa following its accident in July 2009.
If none of these prove fruitful, I’ll try some of the other Models.
Very Best Regards,
Barry
From: owner-commander-list-server(at)matronics.com [mailto:owner-commander-list-server(at)matronics.com] On Behalf Of Moe Mills
Sent: 08 February 2012 07:03
To: Com
Subject: SALVAGE OR DERALICT COMMANDER
COMMANDERLAND'
DOES ANYONE KNOW OF A
680t
680flp
680F(p)
THAT IS EITHER DERALICT OR BEING PARTED OUT?
THANX!
Moe Mills
N680RR
680F(p)
| Quote: | | http://www.matronics.com/Navigator?Commander-List http://forums.matronics.com http://www.matronics.com/contribution |
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yourtcfg(at)aol.com
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| Posted: Mon Feb 13, 2012 8:10 pm Post subject: Lost Hydraulic pressure in flight |
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That is what I always recommend. There should be a circuit breaker/switch, similar to the Beechcraft switch's, installed. Congratulations on handling the emergency well, it doesn't always have a happy ending!! jb
--
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nick(at)container.com
Guest
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| Posted: Tue Feb 14, 2012 10:04 am Post subject: Lost Hydraulic pressure in flight |
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Thanks for your comments
From: owner-commander-list-server(at)matronics.com [mailto:owner-commander-list-server(at)matronics.com] On Behalf Of yourtcfg(at)aol.com
Sent: Monday, February 13, 2012 8:10 PM
To: commander-list(at)matronics.com
Subject: Re: Lost Hydraulic pressure in flight
That is what I always recommend. There should be a circuit breaker/switch, similar to the Beechcraft switch's, installed. Congratulations on handling the emergency well, it doesn't always have a happy ending!! jb
--
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BillLeff1(at)aol.com
Guest
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| Posted: Tue Feb 14, 2012 10:54 am Post subject: Lost Hydraulic pressure in flight |
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No No No! The aux hydraulic pump should only be pulled during an
emergency. It is intended to be operational if you loose hydraulic pressure during
take off and landing.
During take off and landing if the hydraulic system fails due to a broken
line in the landing gear system the main system will fail (the first
indication of a failure of the main system is the nose gear extending) but there
is a reserve that only supplies the brakes, nose wheel steering and flaps.
This system will be available during the landing roll if the main system
fails.
You do not have time to reach over and reset a CB or turn on a switch (this
would require a field approval) once you realize that you have a problem.
However, if you pull the aux hyd CB as soon as you recognize the hydraulic
system failure you will preserve the aux pump supply. This should me a
memory item as far as emergency check list are concerned.
The aux hydraulic pump has no function in extending the landing gear. So,
you should wait until you are on short final to push it in. On the other
hand, why do you need brakes in a 690 anyway!
Ted Smith was a smart guy, don't second guess his intension's about how to
operate his systems.
Bill Leff
In a message dated 2/14/2012 1:04:22 P.M. Eastern Standard Time,
nick(at)container.com writes:
Thanks for your comments
From: owner-commander-list-server(at)matronics.com
[mailto:owner-commander-list-server(at)matronics.com] On Behalf Of yourtcfg(at)aol.com
Sent: Monday, February 13, 2012 8:10 PM
To: commander-list(at)matronics.com
Subject: Re: Lost Hydraulic pressure in flight
That is what I always recommend. There should be a circuit
breaker/switch, similar to the Beechcraft switch's, installed. Congratulations on
handling the emergency well, it doesn't always have a happy ending!! jb
-----Original Message-----
From: nick <nick(at)container.com>
To: commander-list <commander-list(at)matronics.com>
Sent: Wed, Feb 8, 2012 9:16 am
Subject: Lost Hydraulic pressure in flight
Dear Commander Gurus’ :
We started to lose hydraulic pressure in my 690A commander .Pressure went
from 900# to 500# . We followed emergency procedure which calls for the
pulling of the breaker for the aux. hydraulic pump and continued the flight
.Then as is procedure we pushed in the breaker and the gear came down without
a problem..
My question is why not fly with the aux. hydraulic breaker pulled all the
time? This would prevent loss of all fluid if you did not catch the loss
soon enough…
Any comments ? Nick N674NM
From: _owner-commander-list-server(at)matronics.com_
(mailto:owner-commander-list-server(at)matronics.com)
[_mailto:owner-commander-list-server(at)matronics.com_ (mailto:owner-commander-list-server(at)matronics.com?) ] On Behalf Of
Barry Collman
Sent: Wednesday, February 08, 2012 4:08 AM
To: _commander-list(at)matronics.com_ (mailto:commander-list(at)matronics.com)
Subject: RE: SALVAGE OR DERALICT COMMANDER
Hi Moe,
Last I knew:
N55GL, 680F(P) s/n 1200-104, was derelict at Berry Hill, Georgia. Info
from a photo taken in January 2011.
N27GA, 680F(P) s/n 1212-111, was derelict at Corona, California. Info from
a photo taken in February 2011.
N70QT, 680F(P) s/n 1208-109, was being parted out by Mountain Air LLC.,
Marion, Iowa following its accident in July 2009.
If none of these prove fruitful, I’ll try some of the other Models
| | - The Matronics Commander-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Commander-List |
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nick(at)container.com
Guest
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| Posted: Tue Feb 14, 2012 11:13 am Post subject: Lost Hydraulic pressure in flight |
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Bill,
What we were saying was to pull the breaker after takeoff and reset it before landing . This procedure would prevent the TOTAL loss of hyd .fluid if a line was to break and the pilot did not notice the hyd pressure drop on the gage . NIck
From: owner-commander-list-server(at)matronics.com [mailto:owner-commander-list-server(at)matronics.com] On Behalf Of BillLeff1(at)aol.com
Sent: Tuesday, February 14, 2012 10:53 AM
To: commander-list(at)matronics.com
Subject: Re: Lost Hydraulic pressure in flight
No No No! The aux hydraulic pump should only be pulled during an emergency. It is intended to be operational if you loose hydraulic pressure during take off and landing.
During take off and landing if the hydraulic system fails due to a broken line in the landing gear system the main system will fail (the first indication of a failure of the main system is the nose gear extending) but there is a reserve that only supplies the brakes, nose wheel steering and flaps. This system will be available during the landing roll if the main system fails.
You do not have time to reach over and reset a CB or turn on a switch (this would require a field approval) once you realize that you have a problem. However, if you pull the aux hyd CB as soon as you recognize the hydraulic system failure you will preserve the aux pump supply. This should me a memory item as far as emergency check list are concerned.
The aux hydraulic pump has no function in extending the landing gear. So, you should wait until you are on short final to push it in. On the other hand, why do you need brakes in a 690 anyway!
Ted Smith was a smart guy, don't second guess his intension's about how to operate his systems.
Bill Leff
In a message dated 2/14/2012 1:04:22 P.M. Eastern Standard Time, nick(at)container.com writes:
| Quote: |
Thanks for your comments
From: owner-commander-list-server(at)matronics.com [mailto:owner-commander-list-server(at)matronics.com] On Behalf Of yourtcfg(at)aol.com
Sent: Monday, February 13, 2012 8:10 PM
To: commander-list(at)matronics.com
Subject: Re: Lost Hydraulic pressure in flight
That is what I always recommend. There should be a circuit breaker/switch, similar to the Beechcraft switch's, installed. Congratulations on handling the emergency well, it doesn't always have a happy ending!! jb
-----Original Message-----
From: nick <nick(at)container.com>
To: commander-list <commander-list(at)matronics.com>
Sent: Wed, Feb 8, 2012 9:16 am
Subject: Lost Hydraulic pressure in flight
Dear Commander Gurus’ :
We started to lose hydraulic pressure in my 690A commander .Pressure went from 900# to 500# . We followed emergency procedure which calls for the pulling of the breaker for the aux. hydraulic pump and continued the flight .Then as is procedure we pushed in the breaker and the gear came down without a problem..
My question is why not fly with the aux. hydraulic breaker pulled all the time? This would prevent loss of all fluid if you did not catch the loss soon enough…
Any comments ? Nick N674NM
From: owner-commander-list-server(at)matronics.com (owner-commander-list-server(at)matronics.com) [mailto:owner-commander-list-server(at)matronics.com ([email]owner-commander-list-server(at)matronics.com?[/email])] On Behalf Of Barry Collman
Sent: Wednesday, February 08, 2012 4:08 AM
To: commander-list(at)matronics.com (commander-list(at)matronics.com)
Subject: RE: SALVAGE OR DERALICT COMMANDER
Hi Moe,
Last I knew:
N55GL, 680F(P) s/n 1200-104, was derelict at Berry Hill, Georgia. Info from a photo taken in January 2011.
N27GA, 680F(P) s/n 1212-111, was derelict at Corona, California. Info from a photo taken in February 2011.
N70QT, 680F(P) s/n 1208-109, was being parted out by Mountain Air LLC., Marion, Iowa following its accident in July 2009.
If none of these prove fruitful, I’ll try some of the other Models.
Very Best Regards,
Barry
From: owner-commander-list-server(at)matronics.com (owner-commander-list-server(at)matronics.com) [mailto:owner-commander-list-server(at)matronics.com ([email]owner-commander-list-server(at)matronics.com?[/email])] On Behalf Of Moe Mills
Sent: 08 February 2012 07:03
To: Com
Subject: SALVAGE OR DERALICT COMMANDER
COMMANDERLAND'
DOES ANYONE KNOW OF A
680t
680flp
680F(p)
THAT IS EITHER DERALICT OR BEING PARTED OUT?
THANX!
Moe Mills
N680RR
680F(p)
| Quote: | | http://www.matronics.com/Navigator?Commander-List http://forums.matronics.com http://www.matronics.com/contribution |
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cloudcraft(at)aol.com
Guest
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| Posted: Tue Feb 14, 2012 7:17 pm Post subject: Lost Hydraulic pressure in flight |
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I concur. Ted Smith was more than smart. In his last design, the AeroStar, the aux pump was protected and controlled by a breaker switch (similar to what JB was describing) so it could be easily enabled and disabled.In normal ops, I've always advocated "Gear up, aux pump disabled. Gear down, aux pump enabled."
In an abnormal -- plain language, loss of hydraulic fluid -- you'd put the gear down via the pneudraulic extension, bungees and gravity and just prior to touchdown you'd reset the aux pump breaker (or switch) and you'd have a chance at brakes, and nosewheel steering depending on how severe the leak.
You could choose to shoot your wad on flaps, as well, but I don't think you get as much benefit from flaps as you do from brakes in this situation.By the time you're alerted to a hydraulic leak via uncommanded nose gear extension, it's too late!
Remember, for every PhD there is an equal and opposite PhD, so you're getting a few good opinions and options in this discussion.Keith S. Gordonaka Wing Commander Gordon
Life is not simple anywhere. Probably less so elsewhere.KHND RNAV Lead
FAASTeam Lead Rep, Las Vegas
NBAA Access Committee
Las Vegas Airspace Users' Council, NBAA Rep
Las Vegas RNAV Optimization Work Group, NBAA Rep
Las Vegas Class B Redesign Committee, NBAA Rep
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yourtcfg(at)aol.com
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| Posted: Thu Feb 16, 2012 10:07 am Post subject: Lost Hydraulic pressure in flight |
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BILL.............I never thought I would be disagreeing with you, but in this case I respectfully do. The factory is working on a solution for this problem as we speak. The hyd system in all twisty gear Commanders has a flaw. There have been many commanders damaged and at least one totaled (680FLP in Canada) because of this. There have also been many more saved because the pilot had the breaker pulled when the system failed, most recently, Jimmy Rodriguez in San Juan (500B, N106VC, S/N 1). In a perfect world, every pilot would constantly monitor the hyd press gauge and pull the circuit breaker when they see the press falling. In the REAL world, most pilots simply don't devote that amount of attention. Further, as the airplanes are modified and upgraded, the hyd press gauge is oft times moved and placed on the panel where it is difficult for the pilot to see. By the time the nose gear drops (assuming loss of fluid) the aux pump will have long ago pumped the reserve fluid overboard, leaving the pilot with no steering or brakes. Leaving the aux hyd pump energized allows a loss of press for any reason, including loss of fluid, to turn the pump on and empty the reserve that Ted Smith intended to be used for this emergency. It is a flaw or an oversite that has had dire results. As you said, the aux hud pump has no function except to operate the brakes and steering in an emergency. (It will raise and lower the flaps, but should not be used to do so in an emergency, only on the ground). Pilots should ALWAYS check the hyd press gauge before landing. If the press is low, then and only then enable the aux pump. This will ensure there is adequate fluid in reserve to stop and steer the airplane. Caution should be used after landing on piston airplanes (no reverse) as the steering and brakes could fail if fluid is still being lost. Best to clear the runway and call for a tug. All modern Commanders have dual engine pumps and the odds of losing both in a single flight is extremely low. Losing hyd press is almost always form a loss of fluid. Having the aux pump enabled can only make things worse in a real failure. Thanks for all you fine work in Commanderland Bill. Jim Metzger 360-903-6901
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