So, I went ahead and did it anyways.

I'll double check it tomorrow. Based on what I came up with:

8:11 Flight 305 is just west of Lake Merwin near Ariel

8:13 Flight 305 is just east of West Pioneer

8:15 Flight 305 is just slightly east of Battle Ground VORTAC

8:16 Flight 305 makes it westward turn toward the Columbia

8:17 Flight 305 is crossing over what is now 205

8:18 Flight 305 is on the outskirts of Vancouver

8:19 Flight 305 has crossed over the Columbia and is adjacent to the I-5 Bridge

Going to drink more and then come back to this later. Any input is greatly appreciated.

See FJ's post #63402 about time/speed today. Its worth a look. Didn't Coop request the plane to stabilise and slow in his last conversation with the cockpit? (5-10 minutes after our last conversation at 8:05).  It's in some document.
GL.

8:05 pm    t1 305:        
305:      Have attempted on two occasions to make contact with individual he
did not reply. Did not reply. Then used PA system and he said, “Everything is Ok”.
MSP:      Roger.

8:12 pm    t1
305:   Getting some oscillations in the cabin. Must be doing something with
 the air stairs.
MSP:      Roger.

Anderson interview:
Anderson stated that approximately 5 to 10 minutes after the last contact with subject at 8:05 pm, they heard and felt an oscillation of the aircraft and commented that the hijacker could have departed causing the unusual vibration since there had been no change in flight parameters or any other external force which would account for this sudden vibration. They telephoned the company representative ( __________ in ___________) shortly thereafter and stated that the ‘oscillation’ which could have been the hijacker’s departure, would have occurred between 8:05 pm and their call to the company 5 or ten minutes later, the exact time being recorded in the company log. Anderson stated that they had not reached Portland proper but were definitely in the suburbs or immediate vicinity thereof.

Two things:

1. Everyone (including the FBI) continually get confused between the "oscillations' and the "pressure bump". The oscillcations occured first - which were probably Cooper climbing out on to the aftstairs. The "pressure bump" was his actuallly leap from the aircraft. This confusion has caused people to assume that Cooper jumped when the oscillations begain. This is false. He jumped later, when the oscillations would have ended in a pressure bump. We don't know when that pressure bump occurred.

2. We don't know exactly when along the flight path the oscillations or jump occurred. To put it another way - we don't know where the plane was at 8:05 along the accepted flight path to plot a jump spot.

There was no oscillation at 8:05

There was no oscillation at 8:05

I guess the more appropriate question would be - assuming the FBI flight path is accurate - where would the plane be located at 8:05?

My best guess is about 4.5 nautical miles southeast of Headquarters.

What is a ground knot? I don't believe the plane had an average of 217 mph ground speed. that exceeds the optimal speed given to them of a 170 knots KIAS...

Is the chart nautical miles?

You need to use the tacked on scale that is on the FBI charts to measure distances on each chart.  These charts were not duplicated at their printed scale.

Let's go through these speeds again.  It would be extremely helpful if some of the current posters would take a look at those FAA publications on aircraft navigation that I have recommended a few dozen times. 

INDICATED AIRSPEED - This is what the airspeed indicator shows (this assumes no mechanical errors in the instrument and no errors in the pitot and static pressure measurements).

TRUE AIRSPEED - This is the Indicated Airspeed corrected for non-standard pressure and temperatures.  For instance, both the pressure and temperature normally decrease as altitude increases.  There are mechanical type "slide rules" and electronic hand calculators for determining the True Airspeed.  At sea level with standard pressure and temperature, the True Airspeed and Indicated Airspeed are the same.

GROUND SPEED - This is the speed along the aircraft ground track.  It can be calculated by measuring the elapsed time between two points if the distance between those points is known.  It can also be calculated if the True Airspeed and the winds aloft velocity and direction are known.

In the hijacking, NWA engineers in Minneapolis estimated that 170 Knots Indicated Airspeed would provide the maximum range for the aircraft configuration that Cooper specified.  At the 10,000 foot altitude and with the temperature at that altitude, The True Airspeed was about 194 Knots.  This is about 225 MPH in statute miles.

With the wind from the southwest (240 degrees) and about 35 Knots, the ground speed becomes about 180 Knots.  This varies depending on the angle between the nose of the aircraft and the wind vector which changes the the airliner changes directions.

The ground speed was approximately 180 Knots but could be calculated more accurately for each airliner heading.  This is where the 3 Nautical Miles per Minute approximation comes from.

Chaucer, just exactly where does your 165 Knots DME ground speed come from?   

Chaucer, just exactly where does your 165 Knots DME ground speed come from?   

Well, the files indicate different speeds, but the same DME that says 23 miles south of Battle Ground VORTAC also indicates a speed of 165 knots

The simulator is currently not running. I might of mixed up true airspeed with the ground speed data that was displayed at the top of the screen. I don't remember the ground speed being that low..(180)