WorkingSuper,

Did these companies actually trouble-shoot the trouble to its source? Or, did they come in take a quick look at it for free and say "I think this is what is the trouble"? By your brief description I can come with several alternatives of my own.

There is no simple answer to your question. If you paid someone to find the trouble they should be able to prove and explain the trouble to you. If you didn't pay anyone then there is no reason for them to find and tell you what is exactly wrong and what needs to done to correct it.

And no one is saying you can't find help here. I am saying that you are giving too little and/or vague information. If you were in the industry your questions would be worded differently. And you would have included the manufacturer and model of your equipment. Is it doing this at every landing? In each direction? Where are you located?

I am asking these questions so I may try and find a responsible and safe way to assist you.