Originally Posted by
Salusa
Agreed 100% PEASCAKE.
A lack of understanding of the basic theory is prevalent and many times engineers will be chasing a vibe issue by blindly following the process of adjustments given by the more modern equipment.
I much prefer a basic system that just provides a phase angle, track and Lat/Vert IPS.
It's pretty simple to work out manually after that.
177 is a bit old hat but there are newer digital systems that will provide the same basic information with much more accuracy especially track data. Just recently used Dynavibe on a MD500E and was very impressed with ease of use and data provide. First time I used the gear and first time T&B on a 500.
Work it out manually after that and think laterally (pun intended) what is causing the vibe. Apart from routine smoothing /post maintenance etc, vibes are often an indicator of failure of another component.
I will give a nod to AW139 Heliwise and HUMS though. For routine smoothing works very well to follow the suggested moves.
Training is the key and is glossed over usually in my experience when it comes to T&B. It's not a black art, just needs some thought and gets easier the more you do.
I don't recall ever been trained in T&B basic theory and I consider myself to be lucky to have been professionally trained by a major international operator over 25 years ago.
In hindsight it was the old hands who explained the basic theory OTJ and picking it up from there.
How it all began on training..................
After a couple of years using the later balancing machines, I took the basic readings lat / vert / ips from the equipment and gave the figures to (experienced) engineers in the hangar and asked them to plot them on the maintenance manual balance charts (they had to come into my office to plot them) and tell me the balance move to make on the helicopter.
Amazing results, nearly every engineer interpreted them differently (not necessarily wrong) , some could not plot the readings at all, and I mean AT ALL.
Just because you are a fully licensed engineer did not mean you like to track and balance, I think because they were never shown how to confidently, and that there is always a member of a team who likes balancing whilst paperwork is being done by the person who likes to do paperwork and so forth.
For information, I hated avionics, always have and always will, hated pilots reporting an avionic or radio defect to me when my avionic "expert" was not around, (my go to avionics engineers was great at avionics, but no good at balancing.)
So we all have different skills which is great in a larger company, but not so good in a smaller company.
Continuation training, my pet subject, defect reporting in detail, my pet subject.
4 foot square or four square feet......there is a big difference.............
Apologies if we have hijacked the first post.