Pre-J Mooney Jump Start Procedure

[Greg Ellis]

It is amazing that after 17 years of ownership, there are still things to learn about my airplane.  My 1963 C model has the 3 pin external power receptacle.  I just thought that it was standard and not some option.  I found no where in all the logs any entry for its installation.  Interesting.

[M20F]

Hand prop it. 

[cliffy]

Think about taking off with a dead battery!  IF your generator quits you will have nothing to back up electrical power with. 

Your panel will go dead TU!

Really think about it if you are charging off into IFR weather. 

IFR flight is another reason to do the CAW Capacity Check every annual.

Just because it starts the engine (which uses very little capacity) doesn't mean you have enough to get back on the ground with 

when the generator quits!

As a comparison- in the older 737s we "might" have had 30 mins on battery alone. That is why a dual gen failure was a full blown emergency.

How long will it take you (if IFR) at cruising altitude to get down and into a near by airport if the generator quits?

Just something else to think about.  Did you take off IFR with an old battery - that you have no real idea how much is left in it? 

Inquiring minds want to know  :-)

 

[Mooney-Shiner]

On 8/14/2024 at 12:19 AM, cliffy said:

Think about taking off with a dead battery!  IF your generator quits you will have nothing to back up electrical power with. 

Your panel will go dead TU!

Really think about it if you are charging off into IFR weather. 

IFR flight is another reason to do the CAW Capacity Check every annual.

Just because it starts the engine (which uses very little capacity) doesn't mean you have enough to get back on the ground with 

when the generator quits!

As a comparison- in the older 737s we "might" have had 30 mins on battery alone. That is why a dual gen failure was a full blown emergency.

How long will it take you (if IFR) at cruising altitude to get down and into a near by airport if the generator quits?

Just something else to think about.  Did you take off IFR with an old battery - that you have no real idea how much is left in it? 

Inquiring minds want to know  :-)

 

Thank you, Cliffy. Over the years I greatly benefited from your advice, but today I'm a little hurt. It seems that you didn't read me specifically saying that I want to use this procedure for troubleshooting only. Rest assure, no take off will be conducted. I'm still renovating to prepare my plane for an annual, brother. 

[Barneyw]

Hi All

I'm in the middle of an avionics upgrade and have brought up the subject of external power for powering up the aircraft and for possibly jump starting. After much discussion with the electrical guys we have settled on putting in a second contactor in the back wired up to a switch in the cockpit. To that we will connect a 175A Anderson plug using 4G automotive wire. This will be fed into the baggage area with about 3 ft of cable. I have two digitally controlled power packs - one for charging and through a switch on the pack powering the aircraft up providing 13.5V, the other a power booster for jump starting. The booster is only to get you up and running to get to a maintenance facility if the battery has lost capacity but the jump start can be achieved all from inside the cockpit if solo then disconnected with the contactor switch. The switch and contactor will be approved and signed off - what I connect does not form part of the flight performance or structure of the aircraft. Obviously there are limitations with this but we believe it's been sized correctly and should work well. I'd be interested to read what people think.

Cheers

Barney

[Z W]

3 minutes ago, Barneyw said:

To that we will connect a 175A Anderson plug using 4G automotive wire. This will be fed into the baggage area with about 3 ft of cable...Obviously there are limitations with this but we believe it's been sized correctly and should work well. I'd be interested to read what people think.

Cheers

Barney

I don't know what's legal in Australia, but I wouldn't use any automotive wire in an airplane.  Aircraft Spruce sells proper milspec tin-coated wire in all gauges.  It's much higher quality than anything I've seen in an auto parts store, and the coating will not produce toxic gasses in a fire that can incapacitate a pilot:

https://www.aircraftspruce.com/catalog/elpages/unshieldlwire.php

In my K model, the wires feeding the battery, starter, and external power port are all 2 gauge (larger than 4).  You could consult your plane's wiring diagram and IPC to see what gauge wire you have, or verify in the plane.  I would consider using the same gauge wire so that no matter what jump pack you or someone else hooks up, the starter / alternator couldn't overdraw from it and melt the wires you are adding or blow a fuse.  But, that's up to you and your installer to determine possible loads and what gauge you need.

[Barneyw]

51 minutes ago, Z W said:

I don't know what's legal in Australia, but I wouldn't use any automotive wire in an airplane.  Aircraft Spruce sells proper milspec tin-coated wire in all gauges.  It's much higher quality than anything I've seen in an auto parts store, and the coating will not produce toxic gasses in a fire that can incapacitate a pilot:

I appreciate your post and sorry if i didn't make this clear Z W  but I'm not using automotive wires in the operation of the aircraft, those wires I mentioned are inactive and inert during flight. Our processes are reasonably tight here and as I said there are limitations as how this will be used in anger if at all.

[N201MKTurbo]

2 hours ago, Barneyw said:

I appreciate your post and sorry if i didn't make this clear Z W  but I'm not using automotive wires in the operation of the aircraft, those wires I mentioned are inactive and inert during flight. Our processes are reasonably tight here and as I said there are limitations as how this will be used in anger if at all.

It’s the insulation that is the problem. In case of a fire the insulation can burn emitting toxic smoke. For the short run you are talking about, the expense of proper tefzel insulated wire won’t break the bank.

https://www.aircraftspruce.com/catalog/elpages/unshieldlwire.php

It is $11.50/foot

[Barneyw]

Thanks N Turbo I appreciate what you are saying but I don't quite understand the concern. I'm sure there are lots of things that people carry on the aircraft without a second thought which are just as flammable and toxic. It's not a question of cost because hey I'm an aircraft owner, it's more about practicality. I'd be more worried about my seats than 6 feet of automotive wire sitting in the back of the aircraft to be honest which BTW I intend to soon replace with flame retardant foam. I'm not trying to minimise or be churlish in what you are saying because it is a valid point I'm just trying to contextualise why I have done what I have done.

Cheers

Barney

[EricJ]

5 hours ago, Barneyw said:

Hi All

I'm in the middle of an avionics upgrade and have brought up the subject of external power for powering up the aircraft and for possibly jump starting. After much discussion with the electrical guys we have settled on putting in a second contactor in the back wired up to a switch in the cockpit. To that we will connect a 175A Anderson plug using 4G automotive wire. This will be fed into the baggage area with about 3 ft of cable. I have two digitally controlled power packs - one for charging and through a switch on the pack powering the aircraft up providing 13.5V, the other a power booster for jump starting. The booster is only to get you up and running to get to a maintenance facility if the battery has lost capacity but the jump start can be achieved all from inside the cockpit if solo then disconnected with the contactor switch. The switch and contactor will be approved and signed off - what I connect does not form part of the flight performance or structure of the aircraft. Obviously there are limitations with this but we believe it's been sized correctly and should work well. I'd be interested to read what people think.

Cheers

Barney

I think the main risk would be if something inadvertently connected the terminals of the Anderson connector during flight and the switch was inadvertently left on.   That's only two holes in the swiss cheese that could create a significant problem.    I have a (smaller) Anderson connector wired directly to my battery for my Minder, because that's what our airport requires, and it always makes me a little nervous that I depend on making sure the cover is on it when it gets stowed.   This is one of the advantages of the big 3-pin Cessna-style terminals, that they're well protected from anything creating a short-circuit to the battery.    Properly sized Anderson connectors are great, but the terminals aren't  as well protected from something creating a potential short.

I don't see this as a huge thing, and there are probably hundreds of airplanes with similar connectors (like mine) for a Minder and I've not heard of any issues, so take it FWIW.

 

[Barneyw]

Hi Eric

I think you are correct. I have given a lot of thought to this and have paid homage to Dr James Reason. For example, I will ensure that there is a secure cover on the plug and that I will devise a special procedure to ensure I don't do something like leave a switch on. Just an aside to all this I find it interesting that when I picked my aircraft up I had an original AFM and a POH which contained all the cruise control tables, field performance, some normal procedures and a description of the aircraft systems but no emergency procedures, no guidance on forced landings or EFATO. I've talked to ten different pilots and got ten different answers but that is for a discussion on another day. The point is that a certain amount of holes are are close to lining up before we even get started if you get my drift. On the Anderson plug there are three aircraft in the hangar where my aircraft is based and they all have Anderson plugs in fact the avionics workshop and where I get my aircraft serviced have Anderson plugs laying around the shelves so I get the feeling that this plug has been adopted to connect to ancillary external equipment and is ubiquitous.

Cheers

Barney   

[cliffy]

18 hours ago, Mooney-Shiner said:

Thank you, Cliffy. Over the years I greatly benefited from your advice, but today I'm a little hurt. It seems that you didn't read me specifically saying that I want to use this procedure for troubleshooting only. Rest assure, no take off will be conducted. I'm still renovating to prepare my plane for an annual, brother. 

Actually I maybe was not clear enough in my answer as it wasn't directly pointed at you because as you say

you were doing it for troubleshooting reasons.

I was actually pointing (albeit in oblique terms) at the audience in general as there have been times here

in the past when this subject came up and flying off after a jump start was contemplated by some here and in 

other venues. Just like in your car,  jump it and go is thought of but with aviation it has other higher priority concerns when done. 

Sorry if I wasn't as clear as I should have been  I'll try to do better the next time :-)

[Ragsf15e]

5 hours ago, EricJ said:

I think the main risk would be if something inadvertently connected the terminals of the Anderson connector during flight and the switch was inadvertently left on.   That's only two holes in the swiss cheese that could create a significant problem.    I have a (smaller) Anderson connector wired directly to my battery for my Minder, because that's what our airport requires, and it always makes me a little nervous that I depend on making sure the cover is on it when it gets stowed.   This is one of the advantages of the big 3-pin Cessna-style terminals, that they're well protected from anything creating a short-circuit to the battery.    Properly sized Anderson connectors are great, but the terminals aren't  as well protected from something creating a potential short.

I don't see this as a huge thing, and there are probably hundreds of airplanes with similar connectors (like mine) for a Minder and I've not heard of any issues, so take it FWIW.

 

Isn’t there a fuse on the battery minder wiring since it’s normally low current anyway?  I thought my minder connection had a pretty low amp fuse but possibly im wrong?

[EricJ]

1 minute ago, Ragsf15e said:

Isn’t there a fuse on the battery minder wiring since it’s normally low current anyway?  I thought my minder connection had a pretty low amp fuse but possibly im wrong?

Yes, I linked the kit below, which shows an in-line fuse for the minder connection.   So for that it's mostly just the anticipation of not noticing if it's blown when you think it's connected, and/or having to get in the tail to replace it perhaps months after it blew.   For a high-current application like the OP is suggesting, which would use a much larger Anderson connector, a fuse wouldn't be practical (like there's no fuse in the starting circuit, anyway).   Anderson connectors are not awful, they're just not as good as the big three-terminal connectors that many of us have.   

https://www.aircraftspruce.com/catalog/elpages/audioathaik.php

[Z W]

10 hours ago, Barneyw said:

I appreciate your post and sorry if i didn't make this clear Z W  but I'm not using automotive wires in the operation of the aircraft, those wires I mentioned are inactive and inert during flight. Our processes are reasonably tight here and as I said there are limitations as how this will be used in anger if at all.

I understand the plan to be to have an Anderson plug and some automotive wiring running through the plane and connected directly to the battery.  They will be energized by the plane battery, possibly connected to the plane ground, and flying around with you everywhere you go. 

For the cost, I personally would not be OK with that and would get milspec wire, and size them such that if someone who is not you fires the plane up with a big diesel-powered external jump cart plugged in the wires won't melt and risk a fire, but we all make our own choices.  It's a small risk.

[Fly Boomer]

14 hours ago, Barneyw said:

I'd be interested to read what people think.

This sounds complicated.  How often do you "jump start" your airplane?

[Barneyw]

12 hours ago, Fly Boomer said:

This sounds complicated.  How often do you "jump start" your airplane?

Well probably not very often but the plug was dual purpose. Apart from the battery booster I have a separate charging unit which has a dual function 1. charging and conditioning the battery 2. and more importantly providing external power. Before I would undo the access panel and connect the power supply directly to the battery. I don't think it's that complicated - two separate contactors correctly wired and approved the second contactor connected to switch in the cockpit. Again I would like to iterate the wire have no function in the air or carry any electrical load for normal operation. The wires will just sit there and do nothing not much different from hooking up jumper leads. All the other points made on this thread are valid and I appreciate the input.