Wire connectors

[rotorman]

What is this type of connector called? It is used to spice power to the boost pump and also used to connect the landing light wire on the lower engine cowl. Can't find them online. 

[hypertech]

That's a knife disconnect.  Be sure to get the aerospace grade one and you do a good job covering it up for no shorts.  I have not noticed any of those on my plane.

[Bolter]

Since it is broken off, you have the opportunity to replace it with a different connector type.  On my J, the knife connector was the landing light which was disconnected with every cowling removal.  The (aircraft grade) spade type connector I put in was more durable and easier to use.  

[Andy95W]

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

[EricJ]

It's also called a "handshake" connector.

 

[N201MKTurbo]

The knife disconnects are inherently more reliable because they cannot be pulled apart. Spade connectors should not be used for any critical connections. The only reason to use spade connectors is because they are self insulating and don't require insulation tubing over them.

[PT20J]

I believe Mooney practice was to insulate these with a length of clear tubing with lacing chord or tie wraps at at each end and one in the middle to keep them closed.

[A64Pilot]

Talk about 1940’s technology.

There are much better waterproof locking quick disconnects available, the Auto industry led the way on this at least 40 years ago.

[Bolter]

6 hours ago, N201MKTurbo said:

The knife disconnects are inherently more reliable because they cannot be pulled apart. Spade connectors should not be used for any critical connections. The only reason to use spade connectors is because they are self insulating and don't require insulation tubing over them.

If this is the landing light circuit, I would not consider it "critical."  On mine you had to slide the insulation over the connector, and add tie wraps.   

[N201MKTurbo]

12 minutes ago, Bolter said:

If this is the landing light circuit, I would not consider it "critical."  On mine you had to slide the insulation over the connector, and add tie wraps.   

Yea, I'm kind of the pot calling the kettle black. I have insulated spade terminals on my landing light too. If I forget to disconnect them while taking the cowling off, they just pull apart, so it is kind of a feature.

[47U]

11 hours ago, PT20J said:

I believe Mooney practice was to insulate these with a length of clear tubing with lacing chord or tie wraps at at each end and one in the middle to keep them closed.

To visualize, a terminal broke off one of my landing gear position lights.  It was an ugly installation.   

 

[N201MKTurbo]

I used to work for the phone company, way back in the day. Everything was done with lacing cord. Some of those old boys in the central office could lace wires so fast it would make your head spin.

[rotorman]

Thanks for all the inputs. This is a classic case of where you need one or two but can't go to the hardware store for aircraft quality parts. I could get one at Aircraft Spruce for a few cents and then pay $15 for the delivery. Scrounging around would probably be the most cost effective.

[A64Pilot]

2 hours ago, N201MKTurbo said:

I used to work for the phone company, way back in the day. Everything was done with lacing cord. Some of those old boys in the central office could lace wires so fast it would make your head spin.

I’m a big fan of lacing cord over tie wraps. We weren’t allowed to use tie wraps in the Army on wires because of all the broken wires from them.

I’ve also seen a tie wrap almost cut through an engine mount.

[A64Pilot]

21 minutes ago, rotorman said:

Thanks for all the inputs. This is a classic case of where you need one or two but can't go to the hardware store for aircraft quality parts. I could get one at Aircraft Spruce for a few cents and then pay $15 for the delivery. Scrounging around would probably be the most cost effective.

Perhaps someone could point me to an FAR that does, but I’m not aware of one that disallows good quality commercial wire connectors. I only use marine hot glue sealed butt splices for example

[jaylw314]

23 hours ago, Bolter said:

Since it is broken off, you have the opportunity to replace it with a different connector type.  On my J, the knife connector was the landing light which was disconnected with every cowling removal.  The (aircraft grade) spade type connector I put in was more durable and easier to use.  

If you have an LED landing light that has to be wired in one direction, it would be nice to have one wire be a knife connector and the other a spade connector.  That way you'd never get it backwards when you put the cowl back on, which has never happened to me before 

[EricJ]

30 minutes ago, rotorman said:

Thanks for all the inputs. This is a classic case of where you need one or two but can't go to the hardware store for aircraft quality parts. I could get one at Aircraft Spruce for a few cents and then pay $15 for the delivery. Scrounging around would probably be the most cost effective.

It's not a requirement to replace it with the same thing.    You can put something else there, but it needs to be safe.    These days people replace connectors with things like weatherpack or other Amphenol or Molex connectors.   

[N201MKTurbo]

20 minutes ago, A64Pilot said:

I’m a big fan of lacing cord over tie wraps. We weren’t allowed to use tie wraps in the Army on wires because of all the broken wires from them.

I’ve also seen a tie wrap almost cut through an engine mount.

The funny thing is ty-raps were designed originally for Boeing to use on its wire harnesses.

From Wikipedia:

History[edit]

Cable ties were invented by Thomas & Betts, an electrical company, in 1958 under the brand name Ty-Rap. Initially they were designed for airplane wire harnesses. The original design used a metal tooth, and these can still be obtained. Manufacturers later changed to the nylon/plastic design.^[5]

[EricJ]

19 minutes ago, jaylw314 said:

If you have an LED landing light that has to be wired in one direction, it would be nice to have one wire be a knife connector and the other a spade connector.  That way you'd never get it backwards when you put the cowl back on, which has never happened to me before 

Mine are spade connectors and I when I put the LED landing light in I had to mark them carefully to not swap them.    You could put opposite sex spade connectors on the airplane side, but you know if that's done somebody will plug them into each other rather than the light. 

[N201MKTurbo]

24 minutes ago, jaylw314 said:

If you have an LED landing light that has to be wired in one direction, it would be nice to have one wire be a knife connector and the other a spade connector.  That way you'd never get it backwards when you put the cowl back on, which has never happened to me before 

I stagger the length of the two wires. A three inch stagger makes it pretty obvious which way they go.

[A64Pilot]

23 minutes ago, N201MKTurbo said:

The funny thing is ty-raps were designed originally for Boeing to use on its wire harnesses.

From Wikipedia:

History[edit]

Cable ties were invented by Thomas & Betts, an electrical company, in 1958 under the brand name Ty-Rap. Initially they were designed for airplane wire harnesses. The original design used a metal tooth, and these can still be obtained. Manufacturers later changed to the nylon/plastic design.^[5]

History is full of good intentions

[Andy95W]

1 hour ago, EricJ said:

You could put opposite sex spade connectors on the airplane side, 

Careful.  Advocating for heterosexual spade connectors opens a whole other can of worms.

[MikeOH]

1 hour ago, Andy95W said:

Careful.  Advocating for heterosexual spade connectors opens a whole other can of worms.

I'm just glad that connectors are NOT gender fluid; that'd cause real problems

[LANCECASPER]

14 hours ago, 47U said:

To visualize, a terminal broke off one of my landing gear position lights.  It was an ugly installation.   

 

Looks like someone's grandmother knitted that.

[KSMooniac]

Why in the world would the gear condition lights need to have a removable connector like the knife/handshake connectors???  Seems very odd to me.

Deutsch connectors are fantastic if you feel the need to update any connections that get regularly split, like the landing light, glareshield lights, wing tip lights, etc.