I strongly believe in desensitizing horses to everything you can. You never know what you will come across while with your horse and it's up to you to remain relaxed in all situations to pass this confidence onto your horse.
I was very lucky to board at a barn who also owned a contracting company. All of my horses have learned to not bother with heavy machinery and loud noises. Dump trucks, dump gates crashing shit, bulldozers, bobcats, excavators etc are all no big deal no matter how far or close.
This training paid off for me today. I decided to ride my stallion for the first time in about a month. He's a pretty level headed guy. We go out to the front field by the road as it was the only flat and dry area to ride. About 20 minutes the lovely neighbor starts screaming at me that his dog us going crazy about the horse and had hurt itself. How this is my fault and our problem is beyond me so I ignore him and continue on. His dogs are never quiet no matter the time of day or night. They are more then used to the horses. I was also about 300+ meters away from him and his dogs.
Annoyed that he isn't getting a reaction out of me he stats his truck with no exhaust and starts reving it. Still no reaction so he decides to drive down the street ONTO my driveway to continue his rant. I simply told him to train his dog it call the cops but I was doing no wrong. He then decides to start reving his truck again in a failed attempt to spook my horse. Less then impressed when my horse didn't even flinch an ear at him he soured down the driveway and back to his place then continued telling at me to shortly give up and retreat back to his house.
I was so pleased with my boy, he really didn't care about this moron and neither did I. His loud truck was clearly a joke to my boy. He really ouch as super start. We had a lovely ride and finished up about 20 mins later with an excellent first ride of the spring!