Hominid

Robert, You've posted here that wind at 10,000' was 26 or 25-30 knots from the SW. Please share where the info came from. The only thing I've found, other than laments about absense of 10000' wind data, is that agent Carr gave the same magnitude (actually "almost 30MPH").

There's your problem. Don't believe anything you see on TV programs or in the movies.

Robert, I can accept most of what you say (over and over here on the thread) about what Anderson and Rataczak "testified," and definitely re. significance of the light going off momentarily. If they did say all of it, they made a couple of mistakes. When the light came on, the crew would not have felt ear popping or pressure change in the cockpit. It's not physically possible. AND, the later flight test demonstrated that opening the stair caused pressure change that was barely perceptible by instruments but not felt at all. The 7th point misses an important point. I think the crew probably did know when Coop jumped. But we see no evidence that they marked the exact time. AND, knowing when he jumped does not mean they knew WHERE he jumped, which is a much larger obstacle than the drift uncertainty since we do have some wind data.

You're right. They get a lot of training about the terminology and what the words mean. I don't mean that Hannah should have been an engineer, technician or scientist. I've had transcribers who were so specifically for electronics topics. A fast typist can transcribe a lot. But, if the end product matters, the person needs to understand the words. I'm reminded of some court transcripts. Expert, certified transcriber. Yet, things get in the transcript that differ from what was actually said. If the end product matters, it has to be checked.

A transcriber can be an expert at transcribing but be useless at transcribing technical things. People, even transcribers, hear what they think they hear. If a transcriber was presented a recording in an unfamilar language, the transcriber would type all kinds of things that weren't in the actual speech. Same with things regarding any kind of technology. No, I'm not asking how many times or how long Hannah has transcribed. She could do it for a lifetime and not be qualified to transcribe info related to any particular technical topic. It's like, writing for ever doesn't qualify one to write about aerodynamics.

And Hannah has some kind of tech background to enable her to understand what she's hearing? Was that transcription proofed by someone with such background?

So this is, what, second hand interpretation of someone about what they thought Rataczak said?

If your "timeline" says that, you should consider all info in it to be SUSPECT. The message logged at 7:42 indicates the "stew" was already at the cockpit, then "he can't get the stairs down," then "we now have an aft stair lite on."

Try to pay attention when you "read." It depends on what you call a "bundle" and what you call a "packet." The three packets were found together and were stuck together. More than that may have been stuck together earlier.

Three packets were part of a single bundle that was all smashed together. Look on the ground under trees or brush. Leaves and sticks pile up. Their own weight and repeated rains cause it all to be almost cemented together. At one point an FBI agent announced that all the money found at T-bar was from a single bundle.

It is logical that they would stick to 170KIAS over the vast majority of the distance. It is illogical that they would nowhere go slower. It is logical that they would try to help Cooper so he would not get mad and blow them up, and would get off their plane. My optimum driving speed on a road trip is about 60 mph. If ever I could make myself try to keep it that slow, I would go faster or slower at times, but it would have only a small impact on my range or gas usage as long as I departed from my optimum speed for only a small portion of the whole trip.

The first attachment snip is from the logged communications. The entry just below it is an exchange about alternate destinations and weather. What time frame? How many times must I read it? As we all know. The exchange logged at 7:48 began with report from 305 that they were holding 160 indicated "which is approx 5 kts abv the bug." and holding 7 thousand feet and "indctd 160". And MSPFO replied the flight would "not be able to get to Reno in that config." They did not say 305 couldn't make it to Reno if they flew that speed for even a second. They didn't say the crew must never fly slower than 170. As I wrote. Did you read it? I haven't found anything saying that 170 was their target speed other than when they were told it would be the optimum. Really? You don't say (again)? When they were doing 170 at 10K' the TAS was 194kt. What was the TAS when the IAS was 151.1kt? You can calculate something besides 170, right? I know. Do you just cut and paste this in every time the topic comes up? A person not really reading all this might just assume that you must be disagreeing with what I wrote.

Yeah. Deploying your chute is the main problem of anyone who jumps from a plane at above ground level.

The crew of flight 305 helped Cooper. After the incident, Rataczak said something to the effect that everything seemed to go OK as long as they did as Cooper wanted. The NWA incident report indicated "Crew taking pains likewise to gain HJ's confidence by giving him full information and cooperation." It is reasonable that the crew may have slowed the plane down a bit to help Cooper get out. They would not have been able to fly extra slowly for much of the flight because they weren't sure they would have the fuel to get all the way to Reno. But they could have slowed down for a short time at some point they thought would be good for Cooper. An ideal area would have been just after they passed the mountains between Seattle and Vancouver. They knew the rear stairs had been at least ajar for a while. Also, there is a chance they had communication with Cooper before 8:05 by which they knew he wanted them to slow down, and when. The report about the later re-enactment test flight said that the plane was flown at approximately 150 knots, indicated, for the tests. It is logical (scientific experiment wise) that the test would have, to the extent feasible, replicated any conditions that existed at the time "they" thought Cooper probably jumped. Any difference would have to be analyzed to determine its effect. Minimizing differences would therefore minimize analysis, potential for error, and size of errors. So, it is probable that the test flight was at or near 10,000 feet altitude as flight 305 was when Cooper was thought to have jumped. And it is probable that flight 305 was doing about 150 knots, indicated, at around the time Cooper was then believed to have jumped. Tosaw has seemed to get a lot of stuff right. One thing he claimed about the test flight is that it was at the same speed and altitude as flight 305 at the time Cooper was believed to have jumped. This then also suggests that the test flight was at about 10,000 feet and that the reported "approximately 150 knots" indicated airspeed was like flight 305 was doing when Cooper jumped. In fact, the temperature at 10K' during the test flight would have been close to the same as it was when Cooper jumped, because the SEATAC temperature (near the bombing range) was just under 45°F like the ground temperature was when Cooper jumped. Another important condition close to being replicated. 151.4 knots is pretty much "approximately 150 knots," and it works out to be 173 knots true airspeed at 10K' using the SEATAC temperature (7°C) through the middle of the day on which the test flight was made (and standard temperature lapse rate). In posts 436 and 1529 in the old thread, agent Carr said the plane was doing 173 knots when Cooper jumped. He may have meant that this was the speed corresponding to point A in the '72 search-zone map. Or, he may have had info that the speed was close to 173 knots for a few minutes while the plane was over the Vancouver plain. He also referred to 200mph. 173 knots would be 199mph. It would be a mistake to just dismiss statements by Carr. He said some things based on his understanding of things he heard or read. But some things were right out of his case file (like the report on the test flight and his winds data). That case file has data none of us has, including calculations based on such data and better knowledge than any of us has about conditions and events on the night of the hijacking. The airspeed calculated within a few days after the hijacking of course would not have been exactly 173 knots. The calculated figure would have been 172 or 173 "point" something and the value was rounded to 173. The rounding error could be up to +/-.5kt, and this doesn't include errors from the source data that was used in the calculation. So the true value could likely be off by one knot. 170KIAS? NWA did not tell the crew to fly 170KIAS. They only informed the crew that 170KIAS was the optimum speed. Below is the part of the logged communications where this information was relayed. It was also addressed in the same way in the after-the-fact NWA incident report (second image below), which stated that 170 was optimum for range. There is no reason to assume that flight 305 rigidly stuck to 170KIAS during the time period in which Cooper is believed to have jumped. Indeed, flight 305 reported 160KIAS at about 7:47 (a couple of minutes after being given the 170KIAS info), "airspeed in the vicinity of one seventy one eighty" (KIAS, since they had no ability to measure TAS) at 7:53:40 just after leveling off at 10,000', then back to 160KIAS at 8:01. This was the last speed report before the 8:10-8:15 time period in which Cooper is thought to have jumped. The last report before jump time was already less than the optimum 170KIAS. According to the NWA incident report, the speed was 165KIAS 23nm south of the PDX VOR--still below the optimum 170KIAS. So it is likely they were doing about 160 for several minutes before and after Portland. It would have been easy for them to slow down to 150KIAS from 160 at some point during that time.

Can't help about the flow field of engines running or their impact on overall flow field. I suspect that the impact is modest because: the center engine intake is distant and its exhaust is distant and downstream; the side engine exhausts are about 9' to the side and 9' up from the end of the stairs. Some side-to-side impact from side engines could be cancelled by symmetry.

I'll bite. If you passed thru dead air I think the airstream must have been detached from the fuselage. I'm not familiar with the plane but I would suspect from what you say that the aft end is not as streamlined as the 727, which is almost a cone.

It is true. With the rear open no air would be flowing through the cabin except for whatever little bit the air conditioning and pressurization system may have produced. No air flow through because there was nowhere forward for the air to enter. Some air movement could occur. Come in through one area of the door and back out through another. But it would be only slight. One would feel coolness on the face. Light things could flutter. The air movement is like vibration, back and forth, not a steady stream. A dropped feather would fall rather than heading for the door. Air would not have been a valid reason for tethering Tina. It would be in the event she stumbled or fell because of turbulence or something. Air flow in the cabin or high up in the stairwell could not have moved food around in the cabin. The tiny airflow going out the aft door can't be estimated because it would be the result of factors for which we have no info. The main one would be how much air the cabin pressurization system was pushing through. The effect of this would be like you feel in the cabin of any airliner. Get up and stand in the aisle. Do you feel that wind blowing you down the aisle? No. That's how much effect the airflow on flight 305 could have had on things in the cabin.

The attachment shows a representation of the "pressure bump" and, below that, what the "cabin climb rate" guage indications could be if the pressure pulse were long in relation to the leakage time of the guage. The curve is the indication over the time frame of the pressure pulse, and the circles show what the guage indication would look like at different points in time. The positive and negative indications of the guage could have been larger or smaller than shown. They could even have banged up against the max limits on the right side of the guage. The whole sequence could have occurred very quickly, in which case it would seem that the needle jumped down instantly then back up instantly, then back to zero. If it occurred more slowly, this would seem more like a typical (albeit 1-cycle) "oscillation." The response to the pressure bump could easily have been "the oscillation" except for the bump or ear popping not being mentioned along with the oscillations in the logged communications, or the later timing of the bump not corresponding to the logged time of the "oscillations," or nobody ever saying they were the same thing.

I don't believe that 305 was doing about 170 KIAS when Coop jumped. Back in the old thread, Carr said as part of a large post that it was doing 173 knots when Coop jumped. He said a lot of stuff in that post and the DZ jumped on his case about a lot of stuff, but did not discuss that 173 knots. The flight test was reportedly done at near 150 KIAS. At 148 knots, that would have been 173 kt TAS. Although the crew had reason to do that 170KIAS for most of the flight (to have fuel to make Reno), there is no reason to think they would not depart from that for the purpose of getting Coop out.

Luv it. A "Snowmman summmary." Hope ya'll appreciate the work I had to go to scrollin all the way to the right to punch "post."

Two things I've thought strange about the flight test description. One, nothing about altitude. Two, why 150KIAS when other places have said the actual jump would have been at a bit higher. Could different altitude and temperature have resulted in a TAS that duplicated conditions at jump time? Would think that they would have tried to replicate conditions. edit: Maybe their main concern was to replicate the dynamic pressure.

Note that the windscreen in the test pix was blown out only on the left side, whereas both sides were gone in the pic of the stairs at Reno the night of the hijack. There was a pic 19 posted here long, long ago which also had only the left side gone. It must have been from the test also. The stair rebounding up may well have been what initiated the damage to the windscreens. The air pressure would have tried to blow them out like blowing up a baloon. I noticed that the uplock rollers are intact in the pix. If they were knocked off in the hijacking, they were put back by the time of the test. Note that they installed 3 guages in the stairwell. Could have been something they needed to control the stairs, or maybe for measurement of things like "bumps." If anyone ever finds anything from which we could determine the time it took for the stairs to rebound, or rebound and drop back down, I would like to know about that. Good job, Snow, as usual. Does anyone have photos of any of the people from which to identify any of those shown in the group foto?

Let's assume that Dan did not figure out a way to jam something between the struts and the stairwell walls to keep the stairs wide open. Or maybe he just didn't want to harm the crew. As he stands on the step at the pivot, the stairs are hanging down about 20° below the normal stowed position. The air sweeping by pushes up on the stairs enough to keep them from falling farther. At the pivot, the stairs are pushing up on the aircraft fuselage. Think of it like the air is a hand under the middle of the airstair. The weight of the stairs and the force down by the struts are pushing down out toward the end, which pushes the forward end of the stairs up--like a see-saw. The pilot may have adjusted trim to compensate for the upward push and tail pitch-up. Dan is standing at the pivot pushing down with his weight of about 230 pounds. So the stairs are pushing up, and Dan is pushing down. He takes a couple of steps down the moveable part of the stairs, beyond the step at the pivot, and the stairs drop some more. He makes his way on out to the end of the stairs and they drop some more, down to about 33° as shown in the pictures from the flight test. His weight is still pushing down on the stairs the same as before, but the airflow now pushes up on the pivot more than when Dan was not out there. Dan walking out to the end of the stairs has increased the push up on the aft end of the plane, causing the aft end to "pitch up" (again, as flight ops had told the crew to expect). The pilot may have again adjusted trim to compensate for the additional upward force (and tail pitch-up). Creeping out the stairs does not cause any oscillation, which could have occurred only if Dan had hopped his way HEAVILY out to the end (and dealt with the stairs jumping back at him with every hop). It would take "heavily" because "cush" in the lower struts dampen the movement of the stair. When Dan gets down to the end of the stairs, he is not hanging out in the airstream. He is on the stairs, and the stairs function as a wind break. Think of it as hunkering down behind the windshield on a motorcycle zipping along upside down. There is no air blast. It's cold. The air is about -12C° as R99 has pointed out. I'm not sure of what warming there might be from the proximity of the side engines. There would be a little breeziness, but there would not be much windchill because there wasn't much wind. The effectiveness of Dan's wind shield is improved by the screens attached to the handrails. He could stand there all he wanted to watch for evidence of where the plane was. He could even turn partly forward to look for the lights of Portland/Vancouver without any discomfort from wind in his face. Note that, in the later flight test, the men reported that there was no "wind drag" when they were down at the end of the stairs. That is, they were not being blown upon. There is no reason Dan should feel like he must jump right away, or that he can go to the end of the stairs only when he is totally set to jump. Eventually Dan jumps. He doesn't experience a smack as bad as he would have gotten by dropping through a chute at the back of a 727. The airstair has been diverting flow out away from the fuselage. This is different than it would be if someone jumped by diving through an open hole. When Dan comes off the end of the stair, it is pushed up toward the bottom of the fuselage and a pocket of air follows it for a short time rather than continuing to rush aft to smack Dan. There may well have been some other significant factors. But the jump is not the same as just any jump from a jet or just any jump from a 727, precisely because the jump is from off the end of the airstair. When the stair pops up, from Dan jumping off the end, it compresses air between the stair and the stairwell/cabin. The pressure in the whole cabin could have gone up about 1 percent. Doesn't sound like much, but it's more than enough to make the cabin climb rate guage react violently because the guage is estremely sensitive to pressure changes that occur over short periods of time. This pressure pulse is the "pressure bump" felt by the flight crew but not reported via the radio circuit being monitored by the teletype logger. The same pressure pulse (with ear popping) as noted in the later flight test. It was not caused by the stairs shutting against its frame. Copilot Rataczak was later quoted as saying that the AFT AIRSTAIR (ajar) light on the flight engineer's annunciator panel went out momentarily, so the stair apparently did come at least very close to fully closing. But it would not latch because the emergency deployment of the stairs had broken away the uplock rollers and damaged the latch for each roller. If the light went out from the stair fully closing, the control handle must have been in the UP detent. The handle being out of the UP detent causes the light to stay on regardless of whether or not the stair is up. Note that normal instruction for emergency extension starts off by saying to put the normal control handle to DOWN or to try first to drop the stairs in the normal way and to leave the handle at DOWN if that doesn't work. These things were put in the instructions to avoid damaging the latches, which had not been thought of by whoever produced the Transport Canada instructions (which don't include the precaution and say there will be great damage). When the stairs settle back down, they are pushing up on the plane with the same force as before Dan went out onto the stairs. This is less than when Dan was still on the stairs. The force up has reduced because of this, but the force down has reduced because of Dan being gone. It is possible that the jump caused the tail end of the plane to drop back down some, by eliminating the lift caused by the stair being pushed down into the airstream, rather than pitching up more because of the loss of Dan's weight. This would be the end of "a curtsy." Note that the later flight test did not confirm the aft end of the plane pitching up when the test load dropped (as some have thought they heard). It confirmed that the STAIRS popped up then, NOT the plane tail. The flight data recorder should have shown altitude/pressure oscillation, later a gradual pitch change (tail up) as Dan proceeded down the stairs, then the positive pressure bump/pop possibly followed immediately by a pitch change of either polarity. (Remember this when you find the FDR data. To determine this last pitch change, we would need lift and drag info for the lower surface of the airstair under restriction that the airstream would not flow over the upper, forward edge of the surface. The oscillation could have been preceded by a negative pressure bump from the stairs being blown out by the emergency system. We don't have any data from which to determine or even estimate how vigorously the stairs might have opened when the emergency extension system was used.

About 7:41: Dan has dropped the aft airstair. When Dan deployed the airstair, the moveable part of the stairs dropped down a bit. It has been said that it dropped about 20°, which is reasonable and is what flight ops told flight 305 before takeoff at SEATAC. The noise of the engines would have increased. There was no big ear-popping. The pressure dropped very little because the pressure outside the airstairs dropped little. The small drop in pressure was mostly because the dropped airstair created a region to the aft side of the stairs where the airflow past and around the aft part of the aircraft was partially blocked. The slight vacuum on the aft side of the stairs was like the vacuum created behind the rear window of a station wagon or behind the trailer of a big rig zipping down the highway. The vacuum couldn't be very large because the airstair was free to move and because air could easily flow in behind the airstair from both sides. Also, the airstream encountering the airstair was "frothed up" a bit by the tail skid bumper deployed just a little forward of the airstair. Note that the test after the hijacking showed only small pressure change when the stairs were dropped, and that it was perceptible only on instruments (not in the ears). Just as the stairs dropped, there would have been a little puff of air heading aft because of the small pressure drop. After that, no wind. There could be wind blowing out the back of the plane only if air were being allowed in freely somewhere forward. The emergency airstair instruction placard could have been blown off from its place up in the stairwell only if it was already mostly detached and ripped off from waving back and forth (probably leaving part of the placard where it had been). Or, maybe Dan had torn it off to take it to some light when he encountered a problem opening the stairs. There was no perceptible oscillation associated with the airstair being down. It could have happened only if the stair flapped wildly in the breeze. The damping in the lower stair struts precluded such motion. Accounts of airstairs being down in flight have included no reference to such motion or to oscillations. The test flight after the hijacking included nothing like this. There was very little turbulence to cause such oscillation because the aft "cone" of the aircraft is streamlined and the aircraft speed was relatively low. The airstair has a low drag coefficient because it is rounded on the bottom side and not nearly perpendicular to the airstream. The airflow was quite laminar ahead of the stairs except for small scale turbulence caused by the tail skid bumper being down just forward of the aft airstair pivot. The airstream would be deflected smoothly around the stairs because of their rounded and sloped frontal surface. The weight of the airstairs and struts is roughly like that of a person. Had the stairs flopped around after they dropped, they would have flopped around roughly half as much later when Dan got out on them - AND when a man went out on them in the later flight test. In the flight test, the airstairs were "stable" when a man went out on them. The stairs didn't drop enough for Dan to jump. From his position near the top of the stairs he would see only a small black opening maybe three feet high by four feet wide out about 12 feet away (if he had light in the stairwell). There is no way he could dive out through it even from the top step of the moveable part of the stairs. One other thing he could see if he had some light is an "elbow" pointing towards the front of the plane just a little way down the stairs on each side, each elbow being formed by an airstair strut and its associated actuator arm (strut). He would have seen the elbow on the right side of the plane unflexing a little as the stairs dropped initially if he was still facing the controls, both otherwise. And he would have seen both flexing back and forth a little if the stairs bobbed up and down a bit. So Dan took a couple of steps down the stairs. When he got to the step on top of the pivot for the stairs he may have felt it moving a little if the stairs were bobbing a bit. But standing on that step wouldn't make the stairs move. It might further dampen any stair bobbing that had been present. If he pushed hard on the toe of the step he probably would have observed no perceptible movement of the stairs. Just too small of a lever arm in comparison to the length of the stairs out in the airstream. Dan was probably down in the stairwell when the crew tried twice to find out from him if all is OK. He climbs back up to the cabin, gets on the PA, and tells them it is. It's about 8:05. By 8:12 Dan likely would have figured out that he could cause the end of the stairs to drop some by pushing on one or both of the elbows, toward the rear of the plane. He pushes on them, the end of the stairs push down into the airstream, the airstream pushes back and the stairs push up on the stair pivot in the stairwell ("Pitch up" as described by NWA when telling flight 305 what to expect while they were back at SEATAC). He lets go, the stairs come back up out of the airstream, the push up on the pivot reduces, and the aft end of the plane comes back down. Two or three times of this and you have "oscillations." The plane has been "porpoising" under the influence of the rudimentary control surface being manipulated by Dan. The very sensitive cabin "altitude" (pressure) rate-of-change (climb rate) guage at the flight engineers console has given readings that oscillated up and down. It's not the cabin pressure guage. It's the cabin climb rate gage just like the teletype log says. It's three times as sensitive as the pilots' vertical speed indicators and much more sensitive than the pressure guages. NWA people stop using the cabin climb rate term in the future when referring to the event because civilians don't catch how pressure change can be indicated by a "climb rate" guage. OK. Maybe the oscillations were not caused by pushing back and forth on the elbows. It's possible Dan might have caused them by stepping back and forth out a few steps onto the moveable part of the stairs for some reason. Or the oscillation could have been caused by air turbulence. But, for Dan, those moving elbows were right there "in his face." If you or I were there in his loafers (with the loops pulled down under the insteps to keep the loafers from being ripped off when jump time came) we would have had to be pretty dense not to see the elbows and their potential usefulness for getting the stairs down farther. TO BE CONTINUED

I'm sorry, Georger. I don't want this to bother you, so I'll explain how someone can go back and pick out a thing or two from the past to support any idiot viewpoint. ALL, 377 never invited me to dropzone. Shortly before I arrived I was watching the goings on relative to the analysis I had done and 377 had posted here. I noticed that PEK771 said something like it was interesting. I noticed that Georger said something somewhat complimentary about the analysis, mentioned that I might even be reading the goings on, and he said something like he hoped I would post something or answer questions or something. It was just an off-hand invitation. Although the post was under "naturehominid," Georger just referred to me as "Hominid." That's easier, so I just used that when I signed up. And I mentioned that when I thanked him for his earlier gracious comment. Why does this have to be explained as though it were something evil?