Thursday, May 27, 2010

Ahh Yes The Old Relay Quandry!!!!

Those of you who work the Line know what the picture to the right is. For the rest of you, it is a picture of a bunch of relays that live behind the First Officers seat up in the Flight Deck on the 737. Out working the Line you may get calls like "the so and so light is on and it won't shut off" or "I switched power and the Master caution light won't turn on". All of these are real problems to our end users (Pilots) but often not "real" problems in a sense.

I will explain it like this, the 737 must have hundreds if not thousands of relays in it. For any one who does not know what a relay is an electrically operated switch. In other words electricity is supplied to the relay and a switch or contact is made to initiate the flow of electricity to operate a system. Relays are wonderful little and big things that allow the plane to turn on an or off systems very quickly and often times without Pilot or Mechanic actions. Relays must make or break systems thousands of times a flight.

As with any mechanical thing relays some times "hang up" as we say. When a relay hangs up it stays on or off when the power to the coil (the coil opens and or closes the switch) is off. As you can imagine when a relay hangs up it causes erroneous indications or effects on the Flight Deck.

More often than not you can reset a hung relay by simply switching power sources. In other words switch from Ground Power to APU Power and back again. The interruption of power can relax the relay and the system goes back to normal, you look like a hero! There are times, however when that will not work. The next step is not in the Maintenance Manual but it is a time proven technique. Take your flip-flop screwdriver and give the relay a little love tap. This is probably the most used technique out there. If the system or light goes back to normal you have figured it out! There are of course times when nothing but changing the relay will work but, take a look at the picture above and try to figure out which relay is giving you the problem. A look at a wiring diagram will tell you the relay to look for if you are lucky but often there are two, three, four or more relays in a system. Now is the time to take off your High Tech Mechanix Gloves and feel for the HOT relay. Relays that get stuck get hot, quickly!

Changing out the relay is easy enough when you are at the home base with Stores available. But my question is: What to do when you are down line on a road trip and have no relay, no stores, and the next part can not get to you for four or five hours? If the old love tap worked and there are no other problems how do you sign it off? Sure arrangements can be made to have the relay changed downline or at the RON if it is in a maintenance station but, how far should you take it? My personal feeling is if there are no other problems, if you can not get the issue to repeat again, if the plane is going one or at the most two legs and then to maintenance, if the Flight Crew is comfortable with it, than it can be signed off as "Reset system" or "System operates as normal".

What do you think? It's kind of a sticky one, huh?

Monday, May 24, 2010

High Tech Work Gloves

I was thinking about buying a pair of these Mechanix Gloves. I have been using the Tsunami Gloves that SWA supplies us at work and they are ok. I like that they are a lot more flexible than the older leather gloves that we have and they breathe a lot better. I have read some blogs, etc about these types of gloves and most people like them alot. Being oil resistant and better at protecting your hands than the surgical gloves are what attracts me to them. I have never bought a pair, however, and was wondering if any of you out there have used or use them. Let me know.

Wednesday, May 19, 2010

Monday, May 17, 2010

To Drill Or Not To Drill

I like my drill I use at work. I have a Hitachi cordless drill and it has worked for me very well. I am an advocate for using cordless drills, they speed up panel removal, etc. I do, however, get into these moods where I do not want to use my drill to remove panels. Occasionally I like to remove screws by hand, it helps me keep touch with the tactile, hands on nature of our profession. I also notice that there are guys at my job who use the drill to remove and install all sorts of screws into all sorts of things. I have seen guys use a drill to remove and install the little screws that safety the nose wheel retainer ring on. Then they wonder why the thing gets stripped out! I have seen a guy use a drill to put 1/4 turn fasteners in! I mean they only require a 1/4 turn of the wrist for goodness sake!

I think the cordless drill is a blessing to our jobs but people should also be able to use a speed handle or ever a screw driver and I'm convinced that some guys do not know how! We all know that even if you have a panel that has 100 fasteners it is easier, and I think smarter, to loosen each one with a speed handle before trying a drill. We all know this and yet time and time again I see guys blasting away with their drill, cussing when they strip out a screw head, and loathing having to go back and try easy outing the screw.

I know that I am an old fashioned type of guy and that there are cool new easy-outs now that almost always work, but I still reach for the old speed handle. Of course I am also finishing up before most because I do not have to drill out screws because of stripped heads.

This thought was not really about speed handles but rather simply using hand tools now and then. Once a long time ago I was changing a forward position light on a 737-300. I had my speed handle going and my ratcheting screwdriver and I was happy as a clam. One of the other RON mechanics was driving by and asked if I wanted to use his drill motor. I told him no thanks and explained that I wanted to do it by hand. He drove off with a confused look on his face and returned later with a drill motor that he left on my belt loader (that should tell you how long ago it was). Apparently by the time he reached the shop he had convinced himself that I was kidding around!

Call me a glutton for punishment but there are times when using a screwdriver makes me feel like I have accomplished something.

Thursday, May 13, 2010

Old Aircraft Spotlight- The Vickers VC-10

This is a new section I will be adding to the blog. I really like old airliners, so I figured every once in a while I would introduce a new-old airliner.

The first one is going to be the Vickers VC-10. I chose this one only because one of the guys in the shop (BigPart) was looking at it on line.

I don't know much about the VC-10, but it is pretty cool looking. I know it was ordered by BOAC (British Overseas Airways Corporation) and entered service about 1960ish. The plane was very well received by passengers and was the first plane to be certified for "Hands off landing" (CATIIIc). There are several web pages dedicated to the VC-10 and one on the better ones is

Tuesday, May 11, 2010

Our Personal Integrity

In these times of massive oil spills, planes being flown into buildings, wars that start for reasons unknown, the word integrity seems to have fallen clear out of the dictionary. Where did it go and will it be back?

Well, I can't answer that for anybody but me.

I have always maintained my integrity when it comes to my aircraft since my first logbook sign-off. I know there are people out there who have seen me run around acting like a chicken, wearing a HUD cover over my head, or confusing Flight Crews by telling them that I was born without a last name, but I have always kept it serious when it comes to aircraft maintenance.

Maybe its because I have an older brother that is an A&P (no Technician here, thank you), a father who was a WWII fighting Marine, a bit of OCD, I don't know. Maybe all of them put together. I just know when it comes down to it, down to the last screw, I find it necessary to complete the job, whatever it may be, to the best of my ability. If I don't think that's good enough, then I call in someone I trust to look it over and maybe even correct it. I'm not above having my work corrected. In fact, I invite it. My personal integrity is driven by my want of a job well done. When I can do my job safely and it allows the aircraft to leave safely is what I strive for. My integrity knows nothing of making an on-time flight, saving money, or getting back to the break room to catch the end of that great movie. It knows only safety and hard work to make it that way.

I know the A&P's reading this know what I'm talking about and I'm only preaching to the choir here. What I hope is that people either connected with our job or maybe even someone who wonders about us sees this and knows that we care.

We care a lot about personal integrity.

You Want It When???

While I was at work the other day a call came from Maintenance Control. There was a plane headed our way with a #1 engine bleed air issue. We get calls like this all the time and so it was not all that uncommon to have them request that we check it out. The problem came about when they said we HAD to have it fixed in two hours to make a flight to Midway.

A quick check of the history on the #1 engine bleed air system revealed that it had a 45 day history of problems! In other words this bleed air system has been acting up for over a month now and they wanted it fixed in two hours. I thought it was pretty ballsy of them to say we had to get it done, and I let the lead know how I felt about it. Luckily that day we had a guy on shift who is really good with engines and engine systems. He was able to figure out what was wrong and kick the plane out in about an hour and a half. Anyone who has worked on engine bleed air faults knows that often times multiple high power runs are required to narrow down and fix a problem.

Part of the issue is that the 737-700 is using the same bleed air valves and regulators as the 737-300 series. These valves seem to work well on the -300 engines (CFM-56-3) and are pretty reliable. These same components are not very reliable on the -700 engines (CFM-56-7). Boeing has not figured out why this is so, or at least they are not saying publicly why this is so. Through the grapevine we have heard that the -700 engines put out a different harmonic vibration than the older engines and this small vib is playing havoc with the components. Whatever it is they are still working on a fix!

More troubling is the "you have to get it fixed" statement. There is no way that I have to fix anything in an allotted time period. Make sure that you as a mechanic do not fall into this trap. Pressure is part of the job as I have mentioned before, however, when a component has a bunch of history, going back a lot of days, with a lot of different mechanics and parts thrown at it, proceed with caution. Do not let Maint. Ctrl or any one tell you how quickly you should work. In my example it all worked out fine but it could have easily gone the other way with the plane grounded and not leaving until the next morning. Thank God we had Dark Cloud there to work it (yes that is what we call him).

Thursday, May 6, 2010

Remember When Airplanes Were Made Out Of Metal?

I always say "remember when airplanes were made out of metal?" More and more planes are composite these days and soon all the old metal birds will be put out to pasture. In the not too distant future coming across an old metal airliner will be like coming across an old Schwinn Bike, or metal Tonka Toy. Sad really they are beautiful airplanes, this Braniff 727 is gorgeous, sleek, fast, but guzzles gas!! The mechanics who worked on 727s really seemed to enjoy the work, personally I only ever worked 727s in Overhaul (HMV) at Delta and those were beat up old birds! The old metal airliners ruled the skies for what will turn out to be a short era in aviation: the era when fuel was cheap and profits were high. The Glory Days. Thanks Skywalker for the pic.

Tuesday, May 4, 2010

Good Book!

I read this a long time ago and remember enjoying it!

DOWNTIME!! It's Part Of The Game *Guest Post Suggestion!

It happens all the time. I know that at least once a week we mechanics will be sitting in the break room and a ramper or OPS agent will come in for any number of reasons. Inevitably they will say some thing like "you guys have it made" or "you guys don't work too hard". I can't really blame them, they have jobs that require them to constantly be in action. The more they do the more money the company makes in a sense. Since those other work groups are involved with the normal everyday type jobs at an airline they can not wrap their minds around the fact that Airline "Line" Maintenance operates in a totally different way.

We on the Line are paid hourly like everyone else at the airline, that however, is where the similarities end. Every time we leave the office to work a plane we spend money. The more we work, the more money we spend. I'm not talking spending little dollars either, we spend big bucks. At any given gate call we could spend up to and at times over $100,000. Everything we change on the plane is pricey. Of course the other work groups will never be able to understand the concept of staying in the office to save money but that is exactly what a maintenance department should do.

Any time people see us relaxing in the break room they should be excited that we are not out working on a plane and spending thousands of dollars. It's all part of the Airline game, and it's one of the reasons that working the Line is typically more desirable than working in a hangar. Hangar work is more like a regular type of job-the more you work the faster the plane can get back into service and make some money. Sure the same thing applies to a grounded plane out on the Line, but for everyday operations downtime for the Line is money saved for the company.