Old Track & Balance Photos
 

Hi All,

I'm looking for some old pic of the first methods of do a track and balance.

The main one I'm looking for is one of the flag method, where they used a piece of canvas stretched between to poles then marked the blade tips with chalk. They then moved the canvas slowly into the path of the blade tip so the tips are just touching the canvas and did the track adjustments from the chalk markings on the canvas.

If any body has anything please let me know, there might be a small finders fee if the image is hi res enough.

Thanks

Phot

Not sure if you have access to any Bell hard copy maintenance manuals, I do recall some black and white pics of the flag track method on L model, possibly B model. Im on vacation till next monday. I have no access to the manuals or the CD's. If no one else helps you, when I get back to work, I will see if I can find you some pictures.

Ive never done it or seen it done, but damn that looks dicey for sure. And I thought I hated using the RADS.

Hey fellas....for a long time that was the only way....a bit of grease pencil and a tracking flag...or a bit of masking tape stretched between a couple of sticks.

For tail rotors it was a stick with a grease pencil taped to it....and slowly poked into the tail rotor.

There was a technique to swinging the tracking flag into the blades....and not getting the pole smacked out of your hands the wrong way. The wrong way could get you knackered in a split second!

Phot,

not a photo, but have a look at this link-
Rotor **Blade **Tracking

or this one with the diagram
Table 3-2. *Helicopter Vibration Types

Quiet day at the office so time to surf the interweb!

Sorry don't have any pics but have done it with cardboard stuck to a broom handle.

I remember a clasic bush fix for the B47 with a bounce, wrap tape around the end of one blade if the bounce is worse try the other blade and add till the bounce is gone then pull the tape off scew it up then take the blade tip cap off and stuff it inside.

Smooth as:ok:

You can track and balance ceiling fans in the same way. Especially after they have had a few beer cans thrown at them.

A few years back I was qualifying an RTB system on a Mil-8, I was there with the latest and greatest electronic wizardry, but the primary method was the tracking flag method, i.e. chalk on the blades, and some poor sod stood out front with a rubber flap attached to a broom handle.

Oddly enough the ground track carried out with the man with the stick actually left the airacraft smooth as a cat pi$$ing on glass in fwd flight.. ergo, the techy RTB system was pointless!!:}

I'm afraid I don't have any photos though.. sorry.:ugh:

Yep that'd be right
Ive seen them put a huge patch on one tail rotor blade on a Mi-17 and when i asked how they were going to balance it i got the traditional russian response.."Is strong helicopter, no problem!"

The Army Historic Flight at Middle Wallop still use the flag method to track and balance their helicopters. You may be lucky and see them from the Museum of Army Flying if you want a photo. If you want to talk to them, they are at the Weston Heli-days this weekend.

Flag tracking
 

In the Bell 204 M&O manual page 2-79 is a picture in Black and White sowing flag trackinh of the main rotor of the Ball 204. Not sure how to post it on Pprune.

(Totally off topic)
I love messing with my ceiling fans when they need some T&B work. I usually start by using a ruler touching the ceiling and passing the blade paths right next to it to find the blade that is flying higher or lower than the others on average (power off of course :}). Most ceiling fan blades attach to their grips via 3 screws in a Y shape. If you have one flying lower than the rest, add a washer between the blade and its mount at the 2 screws closest to the tip. If its high, add one washer between the blade and its mount closest to the fan motor to lower its tip path. As always keep your blade leading edges clean and pay attention to dust build up on the tops of the blades. Ive seen balance weight method in some high end ceiling fan manuals, but I am a strong believer in getting them in track by adjusting tip path will fix most of your ceiling fan problems. Now if only RADS would come out with some script files for a 52 inch Hunter.

Pray God Hunter never goes to the 500D/E fan head!

Ceiling fans don't go into forward flight, so even a 500 head on a fan wouldn't be too much work :) Just keep those centering bearings clean. Would that fan be a model HU500 for Hunter 500?

Used to do it on Whirlwinds (three Main blades) up to the early 1990's - using a tripod on top of which was a turnable pole. Total height up to about 12 foot tall.
On the side of the pole were two perpendicular legs about 2.5 to 3-foot apart between which was a 4-6 inch strip of canvas mounted on 4 springs.
We would colour the blade tips Red/Yellow/Blue with Wax Crayon. We would also stick masking tape to the edge of the Canvas (so that we could see our marks and not all the others!)
We would set up the positions of the tripod feet on the floor and the approximate angle of the pole to the blade prior to running up the heli (holding up the blade to meet the flag) that took a lot of guesswork out of it!
Jockey would run the heli up and give us the Thums-up when he was ready. We would move the Tripod/Pole assy into place and he would hold the Disk at the mid-canvas level until we'd either told him to stop - or the tape disappeared with someone chasing after it!
After a couple fo ruins we could achieve splits as little as 1/8th inch. Then send it for Flight Checks (using a Scientifica Atlanta clockwork mechanism with Red "wax" tape - but thats another story!)

Happy Memories!
Rigga

Phot,

Try The Helicopter Museum in Weston-super-Mare they have some original equipment on site.


The Helicopter Museum.

Many moons ago, on a small island in the Caribbean, a Bell 212 was being tracked with the pole & flag method. Things went a little awry when the flag was gently moved into the path of the blades. One rotor blade contacted one of the metal tangs to which the springs were attached stretching the canvas flag between the two tangs. The pole was smacked sideways and the two engineers attending the flag were rather shaken.
The helicopter was immediately shut down in order to inspect for any damage to the rotor blades. All eyes were focused on the blades as they slowed down, nobody was aware that in a corner of the hardstanding, an engineer ( I think it was the local chief engineer) was laying in a pool of blood having been cut severely, high up on his inner thigh by the piece of metal that flew away from the tracking pole.
Thankfully, somebody spotted him in time and appropriate medical attention was given.
I can't remember whether the blades were damaged, but this episode just goes to prove that the this method has some hidden dangers!

Somebody else on this forum may have a better memory of this than me?

F43

Hi Phot,
Just knew I had a photo somewhere. :ok:

This was yours truly on the good ship SS Manhattan in the Spring of 1970, on our way through the North Atlantic to the North West Passage.

One blade 'pocket' had been damaged while the S 62 was secured on the helideck in high winds. Caused by the blade deflecting down and then snapping up against the 'tie down' (a canvas bag and cord device).

New blade tracked fairly easily, but we did have to ask the (ship's) captain if he would please sail into wind while we used the flag! :eek:

I have pm'd you in case you would like a larger copy of the pic.







http://i150.photobucket.com/albums/s...le0004-2-2.jpg

...on a small island in the Caribbean
 

flyer43

I must pre-date you at Galeota, when I first arrived there the fleet consisted of 1 x Whirlwind, 1 x Bell 204B and 1 x Bell 206A. Later in my contract, it must have been about late '74 or early '75, the Whirlwind and the 204B were replaced by a couple of Bell 205A-1's (one used machine and one factory-new). As these were single-engine helicopters flying offshore they were fitted with fixed-floats at Galeota prior to being put into service. Inevitably the day came when we had to track the main rotor after some work had been performed and we used a tracking flag for this. I should have known that a Bell on fixed-floats with a possible lateral out-of-balance condition would be a bugger to track with a flag and I was right. I remember moving the flag inward very, very carefully and that I was successful with one blade but the next one sliced right through the canvas and almost tore the flag out of my hands. Luckily, no damage to myself or the helicopter and even more luckily, the notorious chief-engineer-with-no-tolerance-for-mistakes was on time-off that day. Lesson learnt.

Quite a hi-tech flag there! The one we used was a straight-ISH stick cut out of the neighbouring jungle and the remains of a cardboard box held together by a few yards of packing tape.
Still worked pretty well, though!:D

Flag Tracking
 

Exmek, the flag in the pic of the S-62 was exactly the type used on the S-64 and S-65 when I arrived at Sikorsky in mid 1966. Needed six different colored crayons though, and when some of the blades moved around a bit, as happened when the wind was blowing and unsteady, it became a real pain in the dupa for the crewchiefs. Electronic trackers were just being tried out and the ground crews were VERY happy to 86 the flags.

Thanks,
John Dixson