Friday, July 30, 2010

Back In The Day...

Check this guy out! Landing on the snow and ice with a big old heavy metal jet! Back in the day when A&P mechanics were MECHANICS, no TECHNICIANS. When a guy could use a belt loader to check a dent on a horizontal stab with out the fear of incurring a fine from OSHA.When kids feared their parents and a band aid would fix all injuries. In other words: THE GOOD OLD DAYS.

Funny, I don't see any safety vests on these guys. I'm sure these guys could sign off their work with out having "mechanic b" verify that it was done correctly!

I'm pretty sure that I could trust these guys to do their job completely. It looks like a gear swing on the old DC-3. No safety tape, cones, warning lights, etc. If you were too stupid to realize that a gear swing was dangerous and you wandered into the path of the gear, you got hurt and it was your fault.

Look at these guys...they are paying attention to what the instructor is telling them. Look at the instructor...he looks like he would belt any of these guys across the face if they smart mouth him or check their text messages during the class. When did we turn into a bunch of wimps who let the few feeble minded idiots ruin our proud profession?
I love working on planes, I do not love working with what has increasingly been a bunch of spoiled, unknowledgable (is that a word?) meat heads who only want to do the least and think they are owed the most. I advise my kids not to become mechanics not because of the hard work or hours or working conditions, it is simply because I see the direction our profession is headed and it scares me for the next generation of mechanics or as they want to be called-Technicians

Wednesday, July 28, 2010

Good News There is One Manufacturer Who Stand by Their Product!!!

A couple of posts ago I wrote about some work gloves that I bought made by Big Time Products. The gloves in question got pretty beat up the first day I used them and they developed a hole in one of the fingers. Well, the folks at Big Time Products sent me a new pair of the gloves for free!

I still use the older pair and I have even washed them twice to see if they were really washable as the company claims, and they are. I know a lot of you think that buying these things  is extravagant since the company supplies us with a pretty good work glove. What I have found is that the Big Time Products gloves, unlike the ones SWA supplies us, have a padded knuckle area. A while ago when working on a lower anti-collision light I cut my right knuckle very deeply. Of course being a big tough guy mechanic I just wrapped it up and let it heal on its own. I'm thinking that I probably should have gone to the doctor for stitches or something because after two months that thing still hurts but I'm sure all of you have done something similar. Anyway, the Big Time Products glove cushion that area on my hand so I feel that they are a good addition to my tool bag. Check em out when you get the chance.

Big Time Products 20103 Grease Monkey Large General Purpose Work Glove

Wednesday, July 14, 2010

That One Key Piece Of Info

The other day while at work I got to go on a road trip with Maybe-Maybe down to San Jose. The information given to us was that the HDG flag was showing on both the Capt and FO HSI. We gassed up the truck, J-Bird (one of our stores guys) loaded up the parts, we got our tools and were off. For this problem we brought with us an IRU (inertial reference unit), a DAA (digital analog adapter), and both of the overhead panels that talk to the IRU.

This is an IRU from Northrop Grumman. We use a Honeywell system but  no pics avail.

The plane had been taxiing out for departure when the instruments flagged. The flight crew returned to the gate, then contract MX came out, performed a re-align of the IRUs. The flags went away and they signed it off. On push back, this time, the instruments flagged again so they returned to the gate again and called us to go check it out.

Road trips are a perk of being a Line Mechanic. There is a certain amount of pride in knowing that the company trusts us enough to go out and fix planes away from station. There is also satisfaction in the figuring out of what is wrong and using knowledge, and available tools to get a plane that is stuck at an away station back into service. Most guys enjoy road trips and I have written about them before.

Maybe-Maybe and I are of the same mind in that we like to go, fix the plane and come back as quickly as possible. We figured that this would be a quick fix and back to OAK.

Once we got to SJC and read the logbook we found out that the problem only existed on the FOs side instruments. All the instruments: ADI, HSI, RMI, and even the PWS INOP light came on. We began by aligning the plane and checking for any faults in the system. Of course we found no faults and everything worked as it was supposed to. We decide to put the new IRU and DAA in as we were sure the #2 IRU was acting up. When we put the new IRU in we found out that it was "Bad From Stock". There was a fault code that would not reset or go away. So much for a quick trip! We called MX CTRL and they got one headed our way through LAX MX. We could expect it in a little over an hour.

While we waited we kept busy by cleaning the plane (the flight crew left in a hurry and had no time to do it). We also changed some seat belts on another plane that had an issue.

When our IRU arrived we threw it in and got everything working correctly. I called MX CTRL to tell them I was signing off the plane and let them know that it had in fact been working when we arrived hours ago. We did the deed and soon enough a new crew arrived. Maybe-Maybe and I decided that since the plane had returned to the gate twice before, we would wait until it took off to make sure everything was ok. (I think you all know where this is going) The plane boards, pushes back and sits there for like 6-7 minutes. Maybe-Maybe and I are saying "That's it he's broke.....he'll be coming back". We went to OPS and asked the OPS guy to call them. Sure enough he said he was working on the same problem the plane had before.

DAMN! The freaking plane is POSSESSED!!!

They came back to the gate and said that the instruments on the FO side flagged out, but as soon as he put the APU bus back on line the flags went away!! That was it!! that was our piece of info that we were missing!! When the pilots put the plane on the #2 generator the FOs instruments flagged. The #2 generator was not powering the #2 IRU bus!!!

We called MX CTRL and I suggested we MEL the #2 engine driven generator. That was all we had to do all those hours ago when we got there and we could have been done!!

It's amazing how one little piece of info can throw off a whole troubleshooting plan. We had been chasing the wrong problem the whole time! In hind sight we figured the #2 generator must have stopped powering that bus when they first were taxiing out the first time the problem manifested itself. Of course the re-align worked because they were most likely on GRD power or APU power at the time.

We did wait until the plane pushed out to ensure they left. We got to SJC at 12:30pm and finally left at 7pm. A long day of waiting and chasing phantom problems. Oh well, we did figure out what was happening. The plane did finally go make some money.

Wednesday, July 7, 2010

The COAX Connector From Hell

Today at work I got to do a few "firsts" for me. I worked on a plane that had a VHF problem which was traced down to a VHF COAX connector attached to the #1 VHF antenna. I have changed the VHF antennas before and I have monkeyed around with the connectors before. My prior experience with these fun little connectors has been realizing that one was bad and MELing the system since we do not carry the right parts or equipment to fix the thing in OAK.

Since this was a #1 VHF problem it was not MELable, and since the previous shift had traced the problem and ordered the parts I had the relative easy task of putting the thing back together. A first for me, although I did do some COAX crimping at my house for TV cabling.

A little description. COAX  (Coaxial Cable) is a shielded electrical wire. The wire has an inner conductor surrounded by a flexible insulator surrounded by the tubular shielding.

The theory is that the electromagnetic field produced by radios etc. is contained within the space between the insulator and the shielding allowing COAX to be run along other wire bundles without fear of much interference. The thing about COAX on aircraft is that the length of the wire is pretty critical and you are not allowed much slack as far as simply cutting it shorter to allow crimping, stripping, etc.

The connector crimps onto the wire but you have to strip the shielded part of the wire back some so that the wire fits into the end of the connector. Looking at the picture on the right the wire feeds into the narrow hole on the left of the connector. First the barrel is placed over the wire, you push the wire into the connector, making sure it contacts the pin inside, push the shielding down over the narrow thing on the left, slide the barrel down over the whole thing and crimp it. The shielding must contact the connector to ground it out.

Not only was it my first aircraft COAX crimp but they also sent a complete Daniels Strip and Crimp set. Most of you know that Daniels makes all kinds of crimpers that we use on airplanes. They also make pin pushers and pin pullers, hex crimpers, strippers, etc. For this fix the company sent me two Daniels sets! It was pretty cool seeing just one complete set but they sent two. I tried to find out how much they cost but could only find one set on Ebay for $3000.

Any way, we used the hex crimper for COAX, we found the right die block to put into the crimper and squeezed away. When we were done we had a perfect crimp and what do you know the #1 VHF was transmitting again!

One of the things that threw me off for a little was that the wire we were working on had a wire tag on it that said #2 VHF. Apparently Boeing changed the locations of the #1 and #2 VHF antennas on the 737-700s somewhere mid production so the wire tags are all jacked up. Watch out for this one as I can see it really messing people up. I'm not sure why they did not change the tag but, whatever. That was the final first, incorrectly marked wires from the factory.

I have to wonder, this is the second COAX that I have been involved in and I know there have been others, why in such a relatively young aircraft series (the -700s) are we having so many COAX issues? Mines is not to reason why, mines is just to push tin!