Question
QUESTION: i have a bradford pear tree with beatiful fruit on it ,
but when they start getting ripe they rot & and fall off the
tree with a splat.

ANSWER: Bradford pears do not make edible fruit.  It is normal for the small fruit to fall off and should be of no concern at all.  The tree is grown for its fall color and spring blooms.  The fruit is secondary and most people would just as soon the tree not make them at all.  Good Luck.

---------- FOLLOW-UP ----------

QUESTION: SORRY !!BRADFORD WAS A SLIP UP.
I MEANT BARTLETT PEAR.
THEY ROT AS THEY RIPEN ??

Answer
I was wondering about that.  There could be many causes for rotten fruit.  Insects and diseases each can cause this to happen.  Pick off the fruit now and let them ripen inside.  Next year, treat the tree with a fruit tree combination insecticide and fungicide spray.  Your garden center can help you with a selection of a product.  You will have to spray the tree about every 14 days in order to get good edible fruit.  Good Luck.