Maintenance

Warning: This post contains boring technical helicopter stuff. Lots of it...

A view in the tent. The helicopter in the background is the one we rigged.

Flying is a big part of being a crew chief and a lot of fun, but we also work on the helicopters. Here in Al Kut we have both a flight company and a maintenance company. The flight company takes care of much of the routine day to day repairs and inspections while more involved work generally goes to the maintenance guys. On occasion we also get involve is some of the more in depth stuff. Earlier this month I got to work with a couple other repairers on what's called a complete rig. This is the process where all of the flight controls are set up so they operate correctly and have the right amount of travel. It's not something that gets done frequently, only after major work has been done on the aircraft or after flight control components are replaced.

A helicopter has three basic controls - the cyclic, which tilts the main rotor disk in the direction you want to fly, a collective that controls how much of a bite into the air the main rotor has, and the pedals which control the tail rotor to keep the helicopter pointing in the direction you want it to point. These controls transmit the pilots wishes to the main and tail rotor through an impressive number of push-pull tubes, fancy hinges called bellcranks and cables. Because a Blackhawk is a fairly heavy helicopter that requires a lot of force to control it there are also hydraulic systems that provide the muscle to actually move everything.

When rigging the controls the first step is called a "dry rig." This is done with all power off and consists of setting all the various adjustments to a position that will allow you to adjust them in either direction as necessary. Starting from the front the pilot and copilot controls are pinned into reference positions set up by the factory. The connections to the top of the helicopter are adjusted and connected to the first set of hydraulic servos. This first set does much the same thing as power steering in a car - they make it easier to move the controls and reduce some of the feedback to the pilot. Like power steering if these servos fail or are turned off it makes flying the helicopter more work, but doesn't really interfere with flying. The output of these servos connect to the "mechanical mixing unit." This is a nifty little collection of levers and cams that the good people at Sikorsky put into the Blackhawk to make it easier to fly by taking a single input the pilot puts in and coordinating all of the controls to achive the desired result. Yeah, it's magic. The mixer is then connected to the "primary servos" which are the muscle I referred to earlier.

The hydraulic deck where most of the linkages we adjust are. The control rods come up through the deck near the top of the photo, back through the "power steering", into the mixer under the diagonal striped work platform to the primary servos at the bottom. The three gold things are hydraulic pumps, the white thing at lower left is one of the generators and the plumbing at the top right it the cabin heater ducting.

Once all of this is connected and adjusted to neutral settings the primary servos are hooked up to the rotor and hydraulic power is turned on. This is the start of the next part of the process, called the "wet rig." By using certain combinations of the alignment pins and measuring the angle of the rotor blades at different positions we make adjustments to get the right blade setting for a specific control input. This requires taking a lot of measurements and rotating the blades by hand to the correct position for each measurement. It took most of a day with three of us working on it to get this part done.

Adjusting the tension on the cables to the tail rotor

When the main rotor adjustments are completed all of the the controls and linkages up to that point are pinned in the proper test positions and the cables and linkages to the tail rotor are adjusted using the same techniques. Finally all of the adjustment points are safety wired or cotter pinned to make sure nothing changes over time. The entire process took us about three days, which is actually a little on the fast side since we had very few difficulties along the way. Depending on the particular helicopter this is not always the case.

Adjusting one of the push pull tubes on the tail rotor gearbox. The reflection on the tail rotor is just reflective tape for the camera we install to balance the tail rotor.

We then started on the track and balance of the rotor systems. The main and tail rotors are balanced just like the wheels on a car, but rather than using lead weights special washers are bolted on to the hub at certain locations. There is a test set that measure the vibrations at the rotors and computes how much weight needs to be added to each location. Once these are within limits the main rotor is "tracked," which means adjusted so the blades rotate in the same plane rather than flapping all over the place. For this we start with ground runs, then move on to test flights. In our case it took 4 test flights and adjustments to go from a rather bone rattling gallop to nice smooth flight at various airspeeds. OK, as smooth as helicopters get, anyways...

On Station

FOB Delta

It's been an eventful few weeks since the last update, so first of all I hope everyone had a nice Christmas and are looking forward to a happy and safe New Years. We had a relatively trouble free trip over, staying in Kuwait only long enough to recover from the trip over, go to the range to test fire all the weapons and take our in briefing.

The C-17 ride

So after three days we loaded onto a C-17 and flew into FOB Delta, in Al Kut, southeast of Bagdad on the Tigris River.

The birthplace of Abraham

We immediately got started on our environmental training and orientation flights. The environmental training is intended to be an exposure to dust conditions which can cause visibility problems when landing or taking off, but since this is the rainy season the dust at the training site was pretty meager. Since we normally train in the Arizona desert our company routinely operates in high blowing dust areas so we're in pretty good shape. Our local area orientation flights started as soon as we finished the environmental, and consist of flying along with the crews we're relieving to become familiar with our routes and the local procedures. Once these were completed we started flying regular missions, normally with one crew member from the old unit until we completely take over responsibility for the missions which will probably happen before you read this. We've been paying special attention to the way the outgoing unit does things since they've had a year to work the bugs out of their operation. We're planning on implementing much of what they've been doing in our procedures. Why reinvent the wheel?

Inside the CHU

FOB Delta is a relatively small FOB that is pretty well provisioned. The Army has gone with Containerized Housing Units (CHUs) to put people in, and since there are relatively few people here we're in one person CHU's. Kind of like a college dorm in a shipping container. Showers and facilities are in separate trailers nearby, and each "Pod" is surrounded by T- walls - concrete barriers designed to protect against shrapnel from rocket and mortar attacks. Right outside the door is a concrete and sandbag bunker should the need arise. The locals seem to like lobbing in an occasional rocket, although nothing has come close to anything valuable. Since a rocket or mortar draws a forceful response within minutes (sometime seconds) they're more interested in lighting the fuse and getting away than they are in accuracy.

CHUs from the outside - Note the bunkers

The CHU's have 220v power and air conditioning and are almost embarrassingly comfortable. Other facilities include a tiny PX and some fast food places, barber shop, internet cafe, gym and chow hall and a free laundry service, nothing further than about 3/4 of a mile away. There is an infrequently running bus around the FOB, but I generally walk anywhere I need to go. Some people have bought bicycles for a faster trip.

Our work area is about half a mile away and consists of trailers with their own bunkers and T-walls and huge "clam shell" tents used as aircraft hangers. There are a couple of Sadaam era bunkers here as well.

The office

The work day varies with mission requirements. Right now I'm assigned to the reserve mission which puts my shift from 3:00 am to 3:00 pm. We cover the early flights and act as an alert crew for any short notice morning missions. I'll be on this schedule likely for a couple weeks and then rotate on to days. My normal day consists of getting up at 2:00 to shower, shave, etc, walk down to the flight line and check the schedule to see which crew I'll be flying with and what aircraft is assigned. I'll check the logbook to make sure all of the inspections are in order and to see what outstanding problems exist, then go out and prep the helicopter - removing tie downs and covers, preflighting and getting my gear set up.

The line

By this time the gunner has brought the weapons out so we mount those and stow all the gear that gets signed out before each flight. I'll hang around with the pilots to run up the APU (auxiliary power generator) and we'll make sure the proper codes are loaded in the radios, as well as doing the preflight and control checks up to the point where we start engines. At that point the aircraft is "cocked" and we go into the operations center for our mission brief. Normally we have two aircraft assigned per mission. Once the mission brief is complete we have a crew brief, then generally go to breakfast. We'll usually man the helicopter a half hour before scheduled launch so we have plenty of time in case there are any last minute delays. It's always easier to wait for your time hack than it is to try to catch up. A typical mission will have us fly a ring route to several different FOBs acting as kind of an airborne bus route. We'll pick up passengers and cargo that needs to move around southern Iraq and usually stop for lunch at one of the locations, not to mention two to three refueling stops. These flights usually last somewhere between 3 and 5 hours.

Typical flight conditions - lots of smoke and haze

Once we're back we refuel and I'll do the daily inspection while the gunner returns the weapons and gear and the pilots debrief. If there are no new issues on the helicopter it usually takes about two hours to complete the inspections and logbook entries so the aircraft is ready to fly the next day. A daily inspection is good for 14 days if the aircraft doesn't fly, so we always make sure to do a daily after the last flight of the day. That way we find any problems that may come up, and the helicopter is ready to go for the next day's flight. At that point it's usually the end of the work day so it's time to go eat dinner and hit the internet cafe or PX for a bit. On days that I'm not scheduled to fly I'll do maintenance. We have Delta Company which is the maintenance company for the battalion located here, but their job is to handle major maintenance and phase inspections, much of the normal work the crew chiefs handle ourselves.

Soon...

We're close to finishing up at the mobilization station now. In November we completed our Mission Readiness Evaluation which involved a battalion air assault mission, more scenario training and briefings, a personnel recovery exercise and more gunnery (for those who had not yet completed all of the required exercises). The air assault mission was at night using night vision goggles where we put 10 helicopters into a relatively small LZ and inserted 90 troops in a simulated hostile area. This requires some coordination between flight companies to make sure the timing is right, but mostly the emphasis is on safety. Of the 90 troops most had never done an air assault, and many had never flown in a helicopter before. We spent some time with them before the flight to make sure they were familiar with what they needed to know and do, and mostly telling them to take their time. The exercise went flawlessly, even though the evaluators simulated a downed aircraft on the landing zone. This involved setting up security using some of the ground troops and sending our downed aircraft recovery team in who rigged the Blackhawk so it could be airlifted out by a CH-47 Chinook.



We didn't actually airlift it - once every thing was rigged and verified correct it was unrigged and flown back under its own power. Meanwhile we went in and recovered the troops we inserted, again all under NVG's and with no incidents. A good time was had by all. An aside to this mission was learning that a skunk has a three Blackhawk reaction time. As we were lining up to start the air assault we noticed a rather startled skunk trying to get out from under our rotor wash. As we passed over him the Chalk 2 (the second ship in line) saw him and applied a little power to mess with him a little. This caused the now annoyed skunk to do a face plant as he was blown over. Skunks being what they are this guy had enough and sprayed Chalk 3. Everyone (except Chalk 3) was pretty amused by this. We've since noticed a skunk hanging around the barracks, so we've decided it's the same one stalking the pilot of Chalk 2.


In the Personnel Recovery exercise each crew started in a helicopter out in the field and were given a scenario where they had been forced down and needed to move cross country to a pick up point. This exercise had us operating our survival radios, navigating, moving cross country in rough terrain occasionally encountering bad guys. This was quite frankly one of the best training exercises I've ever been in - the scenario was realistic and very little was simulated - we were even able to communicate with the real search and rescue people who monitor some of the high tech equipment we have. This is unusual since it involves using the real assets we would be dealing with in the middle east. While is was some what physical it managed to cover everything from combat operations to land navigation, communications, reacting to IED's, etc. It was also a nice workout.


Finally there were additional gunnery exercises for the people who had not yet qualified in all the required areas. Normally this is a timing issue more than anything else - while day firing can be done while in the training progression, you have to be fully qualified with NVG's before you can shoot with them, so we still had a couple of crew chiefs and gunners that needed the night portion.
The other big training push right now is "environmental" training, meaning desert operations and particularly dust landings and take offs. Our company was largely signed off on these already since we normally train in the Sunoran Desert. Some of the newer crewmwmbers in the company as well as the other two flight companies have been sending crews to New Mexico to get some practice in on the techniques.
With Thanksgiving we were allowed a short break to travel home and spend the weekend with family. A four day weekend followed that was all too short. It was great to spend some time with Her Accuracy. I also managed to get over to Quantum and get a flight in the R-22. It had been three months since I'd flown as a pilot so it was nice to see that while I was a little rusty, I hadn't forgotten anything. I plan to get flying in at every opportunity, the next of which will probably be during my R&R break sometime next year.



We flew back to Ft Sill that Sunday, and on arrival eight of us hopped in a van for the drive down to Ft Hood in Texas to attend a unit armorers school. This was a week long course covering maintenance and repair of small arms for the unit level. The course was pleasant and informative, and I was very impressed with Ft Hood. That's a proud installation and it shows, especially after all the exposure to training commands I've had lately.
We arrived back at Ft Sill after the course with very little left to do - some final work on the aircraft, a little currency flying, and final packing is all we have left to do.

A Ft Sill Update

"Rock Drill" map on hanger floor

It's kind of funny with my background being in Field Artillery that our mobilization site is Ft Sill, the Army's home for all things artillery. I was last here a couple years ago for annual training with A Battery, 2-180FA. While the facilities and support are OK, we are kept fairly isolated from the main portion of the base and have limited transportation. I also have to admit to being confused as to why this is an aviation mob site. The area is not particularly well suited to training for either the desert (Iraq) or mountain (Afghanistan) environment, and aside from the fact that there is an airfield here there doesn't seem much to commend it. There are quite a few ranges, but most are dedicated to howitzer and rocket fire. It seems to me that Ft Hood in Texas, Ft Carson in Colorado or Ft Rucker in Alabama would make more sense since they actually have the infrastructure built in. This is particularly evident for terrain flight and air assault training where the area available is limited. The aerial gunnery options are also tight compared to the Barry Goldwater range in southern Arizona that we're used to. This is not to say that the training is ineffective, it's just somewhat limited by the environment. Of course, we also don't have the same preflight hazards here as back home.

I think this guy wanted to go for a ride

Once we leave the military reservation for cross country flights the local area does work well for us, although I'm not used to having the machine guns out when flying over civilian populations. We don't carry ammunition on these flights, but I really don't like training the weapon anywhere people might be even unloaded. We have flow several missions to local airports practicing what are called ring routes where we deliver people and cargo where they're needed. These flights usually consist of three to four hours of flight time with landings at several fields and are used to evaluate our ability to execute missions on time with minimal notice while having to deal with real and "notional" maintenance and scheduling issues. Our evaluators also throw in simulated mortar attacks and other environmental problems to stress the system. While is seems trivial, just the mechanics of getting helicopters, weapons and crews all together and ready to go at the right time takes some practice. Once all the pieces are in place the crews are evaluated during the flights for their ability to perform the various crew functions, communicate effectively and operate as a team in simulated combat conditions.

As a crew chief once we're on our mission profile the primary responsibility is maintain airspace and surface surveillance, sometimes referred to as looking out the window. Most of the area we fly over is farm country, and from the air it's beautiful country - one can see how a farmer gets so attached to their land. It's also a nice break when we get to talk with some of the locals during fuel stops. The high point for me so far was a stop at Duncan (waving to Bag Blog) where we were met by three local children who were clearly excited by our arrival, but demonstrated excellent airport manners by staying well away from the ramp area.

A photo op with our young visitors

Even when we invited them to come look at the helicopters they ran off and got permission from their father first, and asked very politely if it was alright to take pictures of us. I'm not sure who enjoyed the experience more, them or us.

Once the flying and maintenance for the day is done, we've still got things that need to be done. Nearly everyone has responsibilities that need to be taken care of in addition to our primary work. Safety, hazardous materials handling, training - lots of little behind the scenes things that can be tedious, but need to be done.

Tommy working on driver training documentation after hours

This coming week we'll be doing night missions so I'll be back on the night vision goggles. It will be interesting to see what kinds of missions we get.

The Mob Station

We've wrapped up our state training time now, and are officially mobilized on Federal orders. The last month has been busy, occasionally frustrating, but mostly productive. From a practical standpoint a National Guard aviation unit can be broken down to three type of soldiers. What most people think of for the Guard are "M-day" soldiers. These are the one weekend a month, two weeks annual training guys. The next group are AGR. These are full time National Guard soldiers in key positions. They can be thought of as kind of a cadre responsible for most of the organizational and planning tasks necessary for the unit to make their training time as effective as possible. Finally there are the technicians. While it's not a requirement for the job, many technicians are M-day soldiers whose full time jobs are maintenance and support government positions. When the unit is between drills these are the guys who do the work to keep the helicopters flying. Now that we're on an active duty status we've been working on two major tasks - first integrating the M-day soldiers into the full time maintenance process to clear as many "gripes" as possible on all the aircraft, get all the inspections coming due soon done so as not to interfere with our training requirements at Ft Sill, and to make sure all the helicopters are ready to go. The second task is to get the air crews current. While the Guard provides for additional training periods for aircrew, due to their full time jobs not everyone can take full advantage of the opportunity. These soldiers have been the priority for flights. Of course we've continued training on mobilization tasks, qualified everyone on aerial gunnery, had a PT test, etc. We also had the opportunity to spend a little time with family before leaving for Ft Sill.
The flight out was unremarkable taking about eleven hours of which about seven hours were actual flying time. (The video above of our departure was put together by Her Accuracy. Nice job, Sweetee!) We did stop a couple of times for fuel and lunch along the way. Unfortunately when we arrived we had to immediately proceed to an in briefing. I guess it's good to get it out of the way, but I'm pretty sure none of the flight crews retained any of the information. In addition to the thirty Blackhawks of our battalion there are a half dozen or so Chinooks from Ft Eustis here that are mobilizing for northern Iraq.
Our first few days here consisted of verifying paperwork, which went quickly, getting our RFI (Rapid Fielding Initiative) issue of flight suits and enough cold weather gear to keep us toasty in the outer reaches of the solar system. This confirmed to me that we are indeed going to the desert. My last deployment was to an area where "cold" meant 50 degrees, and they issued us gear better suited to the arctic.
The weather at Ft Sill didn't cooperate for the first week we were here, severely limiting our flying. This week the skies have cleared up and we've resumed crew training flights. Since I'm already qualified I'm only flying at night with the night vision goggles supporting pilot currency flights. We'll be starting our mission and evaluation flights before too long, until then I'll be doing a fair amount of maintenance work. We still have some ground training to do yet as well. Much of it is of limited value to an aviation unit, but after some regrettable training deficiencies that became apparent early on in Operation Iraqi Freedom, the Army has decided that every one gets additional training on common soldier tasks prior to deploying.

Channel 3 news coverage of the departure.