You wrote: “The lifting happened in a few MINUTES, not seconds.”
Not true. The Army incident report that Coyne and the crew filled out and signed immediately after the incident says: “SSG Yanascek observed a red
light on the east horizon, at ninety degrees to the flight path of the helicopter. Approximately 30 seconds later SSG Yanascek indicated the object
was converging on the helicopter at the same altitude at an airspeed in excess of 600 knots and on a midair collision heading.”
After taking over the controls and initiating a shallow dive to avoid a midair collision (SOP, by the way) a radio call was put in to the nearest air
traffic control facility (Mansfield Tower) asking if any high performance aircraft were in the vicinity.
The report goes on to add: “The crew expected impact from the object instead, the object was observed to hover momentarily over the helicopter and
then slowly continued on a westerly course accelerating at a high rate of speed, clear west of Mansfield Airport……”.
Here, the term “hover” obviously means that the object was stationary relative to the helicopter, not the ground.
In other words, the “object” (not “aircraft’) was only in proximity to the helicopter and matching speed with it “momentarily”, not “minutes”. Furthermore, when the object was in proximity, the crew all agreed that it was ABOVE the helicopter.
The crew did not state how long it took from the time they determined it was on a collision course until it was overhead, but given the high rate of
closure, and the fact that they had to make a brief radio call, it was probably no more than 30 seconds or so. So, as I read it, the entire sighting
took maybe a minute and a half, from eastern horizon to western horizon, during which time it was overhead and matching speed with the helicopter for
a few seconds.
You went on to write: “Coyne himself stated that the altimeter showed a rate of climb of 1000 ft/min.”
True, and I assume that’s where you got the erroneous notion that the encounter took minutes instead of seconds. What you’re not taking into account
is the physics of how Rate of Climb (ROC) indicators work. ROC indicators use the same pitot tube and static port pressure inputs that the airspeed
indicator and altimeter use. They are designed to calculate-using analog logic (springs and bellows)-the direction of change of altitude (up or down)
and the approximate magnitude of that change. However, the response time of a ROC indicator has a time delay deliberately built into it for the
purpose of filtering out high frequency noise (such as you get when you are flying in turbulence or are making abrupt control changes). The time
constant for a barometric ROC instrument is typically about 8 seconds. In pilot basic training, we are taught that when flying in turbulence or in
the presence of abrupt altitude changes, the ROC is inaccurate and cannot be relied on. A more accurate ROC estimate can be made by the pilot
measuring the time between altitude hacks using (for example) the cockpit clock. The only conclusion that can be drawn from the 1000 ft/min reading of
the ROC indicator is that the helicopter was rising at a high (but indeterminate) rate.
In an interview given with the Mansfield News Journal a couple of weeks after the encounter, Coyne was quoted as saying:
“I had made no attempt to pull up,” he said. “All controls were set for a 20 degree dive. Yet we had climbed from 1,700 to 3,500 feet with no power in
a few seconds with no g-forces or other noticeable strains.”
In the same interview, Jezzi was quoted as saying: “It took just a couple of seconds.” “I remember looking up through the ceiling and I saw a white
light moving over top of us. I followed it to the left horizon, where it disappeared.”
Both pilots agreed that the altitude increase was about 1850 feet in a few seconds.
a reply to: Nickless