We live north, no more than three miles (as the crow flies), from PDX, perpendicular to the generally east-west alignment of the two major runways, and about 300 feet higher than the runways. We are buffered by the open water of the Columbia River, homes, and several stands of very tall Doug firs. We regularly hear aircraft take off and land. During overcast conditions the aircraft sounds are magnified greatly as the sound bounces back down from the clouds. We can easily tell when an aircraft lands during overcast conditions because the reverse thrust sounds are very loud and quite distinct, compared to take off thrust.
But when the National Guard takes off on their daily patrols, it’s a whole new ball game. Quite off it’s impossible to carry on a normal outdoor conversation as the takeoff sounds are several magnitudes louder than commercial aircraft. Also, the Guard aircraft take off two at a time in at least two to four successive takeoffs. At night when the normal ambient road traffic noise is diminished, the Guard takeoffs will even shake house windows.
I’ve been to Boeing Field and stood no more than 100 feet from the runaway as new Boeing jets take off and land. None are anywhere as loud as the National Guard jets from three miles away. (We once watched a new all white, unmarked 747 take off from Boeing field. It was so whisper quiet we could carry on a normal conversation right at the end of the runway as the pilot applied full thrust for takeoff. When we later asked at the visitor center we were told, paraphrasing, “Boeing doesn’t talk about that particular 747.”)
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