Total electrical failure - (hypothetical)

On Thu, 24 Mar 2005 15:46:41 -0800, "C J Campbell"
wrote:


"Michael" wrote in message
roups.com...

That's because they lack vacuum
Nonsense. Most of them have backup vacuum instruments and even have
dual
vacuum pumps, which older airplanes lack.

What piston single has backup vacuum and backup electric?

All of the Cessna G1000 airplanes.

I'd have to go check my POH to be sure, but I'm pretty sure that the
G1000 Cessnas don't have 2 pumps. It has a single AI and a vac pump
as a backup to the glass system. As for the electrics, depends on
what you classify as "backup electric". If you're talking fully
redundant alternator and feed, it doesn't have that either - it has a
backup battery good for ~30min of reduced functionality (if memory
serves the PFD, 1 com, 1 nav, 1 GPS).

The 172SP has 2 vac pumps. Course, the plumbing goes through 1 T
connector before the firewall, but still. Fails the backup electric
test though.

"Peter Clark" wrote in message
...
On Thu, 24 Mar 2005 15:46:41 -0800, "C J Campbell"
wrote:


"Michael" wrote in message
roups.com...

That's because they lack vacuum
Nonsense. Most of them have backup vacuum instruments and even have
dual
vacuum pumps, which older airplanes lack.

What piston single has backup vacuum and backup electric?

All of the Cessna G1000 airplanes.

As for the electrics, depends on
what you classify as "backup electric". If you're talking fully
redundant alternator and feed, it doesn't have that either - it has a
backup battery good for ~30min of reduced functionality (if memory
serves the PFD, 1 com, 1 nav, 1 GPS).

I had already pointed that out in the post that Michael was replying to.

Cessna's web site says the plane comes with a dual vacuum system.

Peter Clark wrote:
What piston single has backup vacuum and backup electric?

All of the Cessna G1000 airplanes.

I'd have to go check my POH to be sure, but I'm pretty sure that the
G1000 Cessnas don't have 2 pumps. It has a single AI and a vac pump
as a backup to the glass system.

OK, that makes more sense.

As for the electrics, depends on
what you classify as "backup electric". If you're talking fully
redundant alternator and feed, it doesn't have that either - it has a
backup battery good for ~30min of reduced functionality (if memory
serves the PFD, 1 com, 1 nav, 1 GPS).

So no protection against bus fault, but at least it protects against
the loss of a master contactor or battery.

The 172SP has 2 vac pumps. Course, the plumbing goes through 1 T
connector before the firewall, but still. Fails the backup electric
test though.

OK, so there are not actually any Cessnas that have dual vacuum and
backup electric.

That's what I thought.

Michael

On Fri, 25 Mar 2005 07:11:40 -0800, "C J Campbell"
wrote:


"Peter Clark" wrote in message
.. .
On Thu, 24 Mar 2005 15:46:41 -0800, "C J Campbell"
wrote:


"Michael" wrote in message
roups.com...

That's because they lack vacuum
Nonsense. Most of them have backup vacuum instruments and even have
dual
vacuum pumps, which older airplanes lack.

What piston single has backup vacuum and backup electric?

All of the Cessna G1000 airplanes.

As for the electrics, depends on
what you classify as "backup electric". If you're talking fully
redundant alternator and feed, it doesn't have that either - it has a
backup battery good for ~30min of reduced functionality (if memory
serves the PFD, 1 com, 1 nav, 1 GPS).

I had already pointed that out in the post that Michael was replying to.

Cessna's web site says the plane comes with a dual vacuum system.

It would appear that their website is incorrect when referring to the
NAVIII (G1000) option. The 182T NAV III POH page 7-63, "VACUUM SYSTEM
AND INSTRUMENTS" states in part "The vacuum system (refer to Figure
7-9) provides the vacuum necessary to operate the standby attitude
indicator. The system consists of one engine-driven vacuum pump, a
vacuum regulator, the standby attitude indicator, a vacuum system air
filter, and a vacuum transducer."

There are two pumps in the NAV I and II aircraft, both C172 and C182.
I expect my G1000 172 will not have the backup pump like my current
172S NAVII does.

P

"Peter Clark" wrote in message
...

Cessna's web site says the plane comes with a dual vacuum system.

It would appear that their website is incorrect when referring to the
NAVIII (G1000) option. The 182T NAV III POH page 7-63, "VACUUM SYSTEM
AND INSTRUMENTS" states in part "The vacuum system (refer to Figure
7-9) provides the vacuum necessary to operate the standby attitude
indicator. The system consists of one engine-driven vacuum pump, a
vacuum regulator, the standby attitude indicator, a vacuum system air
filter, and a vacuum transducer."

There are two pumps in the NAV I and II aircraft, both C172 and C182.
I expect my G1000 172 will not have the backup pump like my current
172S NAVII does.

Well then, thank you. I appreciate that.

On Fri, 25 Mar 2005 20:12:32 -0800, "C J Campbell"
wrote:


"Peter Clark" wrote in message
.. .

Cessna's web site says the plane comes with a dual vacuum system.

It would appear that their website is incorrect when referring to the
NAVIII (G1000) option. The 182T NAV III POH page 7-63, "VACUUM SYSTEM
AND INSTRUMENTS" states in part "The vacuum system (refer to Figure
7-9) provides the vacuum necessary to operate the standby attitude
indicator. The system consists of one engine-driven vacuum pump, a
vacuum regulator, the standby attitude indicator, a vacuum system air
filter, and a vacuum transducer."

There are two pumps in the NAV I and II aircraft, both C172 and C182.
I expect my G1000 172 will not have the backup pump like my current
172S NAVII does.

Well then, thank you. I appreciate that.

No problem, glad I could be of assistance.

Y'All,
I do believe my 'real' total electrical failure situation deserves mention.
Situation: Flew a 180 h.p. Yankee Trainer with a 14 gallon fuel tank
into Nut Tree, Vacaville CA. just as it got dark. Needed a ride to
CCR a distance of about 30 miles. While I tied down the Yankee
the other pilot got his Grumman Tiger preflighted nearby.

We took off and at about 600' we had a total electrical failure.
At that moment before I even had a chance to ask for his flashlight,
the pilot told me that the batteries had died during the preflight.

So I learned how to fly without any instruments at all. It was a clear
night so I had no difficulty returning to the airport with a good safe
landing judging speed and power by air and engine sounds alone.

Surprise of the night was that on clearing the runway I crossed right in
front of a taxiing twin heading out for takeoff. I have always wondered
just what was said in that cockpit.

Lessons learned:
---Bring your own flashlights.
---Learn to 'index' your power settings by feel and sound.
---Learn to 'index' your airport patterns for some standards
---Get Lucky if you want to be an old pilot.
---I was able to hitchhike a ride to CCR by telling my story.

Gene Whitt

"Peter Clark" wrote in message
...
On Tue, 22 Mar 2005 06:26:58 -0800, "C J Campbell"
wrote:


"MJC" wrote in message
.. .
Well, that's not what I had in mind with the original description.
All
of those instances have one thing in common; that the people who
survived
were ALL still inside some part of the airplane.
What I was looking for was a "naked" fall (not inside a part of an
aircraft) of 20,000 without anything to hang onto.

MJC

So was I. However, that site lists some of those as "free fallers."

And as CJ pointed out, same site,
http://www.greenharbor.com/fffolder/ffallers.html has entries for two
falls from 20k and 22k, outside of the destroyed airframe, and
survived.

Unfortunately, the site lacks any documentation for those claims. They
*might* be true, but all the site itself tells us is that someone somewhere
in the world says so on some unspecified basis.

--Gary

On Sat, 30 Apr 2005 15:28:18 -0400, "Gary Drescher"
wrote:

"Peter Clark" wrote in message
.. .
On Tue, 22 Mar 2005 06:26:58 -0800, "C J Campbell"
wrote:


"MJC" wrote in message
. ..
Well, that's not what I had in mind with the original description.
All
of those instances have one thing in common; that the people who
survived
were ALL still inside some part of the airplane.
What I was looking for was a "naked" fall (not inside a part of an
aircraft) of 20,000 without anything to hang onto.

MJC

So was I. However, that site lists some of those as "free fallers."

And as CJ pointed out, same site,
http://www.greenharbor.com/fffolder/ffallers.html has entries for two
falls from 20k and 22k, outside of the destroyed airframe, and
survived.

Unfortunately, the site lacks any documentation for those claims. They
*might* be true, but all the site itself tells us is that someone somewhere
in the world says so on some unspecified basis.

Um, googling Alan Magee brings up an article in the Free Republic
reprinting (reposting?) an article from the Albuquerque Journal which
references a 1981 Smithsonian Magazine as the original source of the
story.

Even a perfunctory googling of the 1st name on the link I gave (Lt.
I.M. Chisov) brings up the same link
(http://209.157.64.200/focus/f-news/1071076/posts) and references
Hecht, Eugene. Physics: Calculus. 2nd ed. p. 85 as their source. The
209blah link is the third one Google brings up...

"Peter Clark" wrote in message
...
On Sat, 30 Apr 2005 15:28:18 -0400, "Gary Drescher"
wrote:

"Peter Clark" wrote in message
And as CJ pointed out, same site,
http://www.greenharbor.com/fffolder/ffallers.html has entries for two
falls from 20k and 22k, outside of the destroyed airframe, and
survived.

Unfortunately, the site lacks any documentation for those claims. They
*might* be true, but all the site itself tells us is that someone
somewhere
in the world says so on some unspecified basis.

Um, googling Alan Magee brings up an article in the Free Republic
reprinting (reposting?) an article from the Albuquerque Journal which
references a 1981 Smithsonian Magazine as the original source of the
story.

Even a perfunctory googling of the 1st name on the link I gave (Lt.
I.M. Chisov) brings up the same link
(http://209.157.64.200/focus/f-news/1071076/posts) and references
Hecht, Eugene. Physics: Calculus. 2nd ed. p. 85 as their source. The
209blah link is the third one Google brings up...

I'd found the physics-text reference via Google, but that doesn't seem like
an authoritative source for a news story. The Smithsonian Magazine reference
looks more promising; thanks for the pointer.

--Gary