I'm not sure how much air you might be referring to. There should be 1/2 to 1 inch headspace at the top of jars before the lids are placed on them. That may change a little after they are processed. Applesauce can expand due to trapped bubbles and may fill the jar completely. If a lot of air is trapped, the apples sauce can ooze out of the jars during or after processing. If the jars boiled too hard during processing, some of the liquid may syphon out so there may be low enough liquid that some of the fruit is exposed in the jar. It may also have overflowed if the jars are lifted out of the canner before allowing them to sit 5 minutes so they stop boiling before being removed from the canner.
If the jars are sealed, they should be safe. If part of the pears is exposed, it could darken over time, so you might eat those jars first. In the future, you might adjust the burner once the canner boils, so that it stays at a steady gentle boil, not so hard that the jars rock. That will help prevent the overflow. Also remember to remove bubbles from the jars by running a plastic knife or chopstick around the edge of the jar before putting the lids on. That might help, too.
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