Recommended Posts
Farflung 0
Good catch on the wing vortices hangdiver. I’m pretty sure that those jet engines aren’t counter-rotating but as everyone on this thread knows, those effects would be mitigated by the lack of asymmetric thrust therefore eliminating any concerns about a critical engine.
As Robert99 adroitly pointed out, the turbulence from extended gear at Flight 305’s airspeed would be minimal since velocity is one of those ‘Root Mean Square’ equations that I never understood (too busy being cool). I realize that the drag landing gear produces below 200 knots is minimal but my penis demands a fully retractable system like those on Beech Bonanzas and Cessna Cardinals. Having a retractable plane makes me more manly manish on the macadam. It’s just my way of scent marking others on the airfield and letting them know who the Alpha Male Silverback is in this neck of the woods. Strange how the numbers of people participating in General Aviation for fun, keeps going down, I just can’t figure it out.
Perhaps a better example of aerodynamic drag would be the ubiquitous US Postal Service and FedEx trucks that have the aerodynamics of a brick. Apparently at speeds below 25 MPH there is virtually no advantage to streamlining and these vehicles spend the vast majority of their life well below that.
Where velocity becomes critical here is with the jets that FedEx utilizes to move parcels across the country making deliveries in just one day. Much the same way the Postal Service employees gun down co-workers and fellow citizens in a fit of seething rage barely contained during the decades long fermentation triggered by the realization of a squandered life spent sorting Harriet Carter and Publisher’s Clearing House catalogs while counting down the seconds till retirement and realizing the futility of it all.
At least that’s my understanding of low velocity drag.
Robert99 50
QuoteI went to several skydiver websites where they
describe bailing from jets (incl the 727) and nobody
reported any problem due to engine blast etc ...
so unless Rat did something intentional to give
Cooper a 'jet blast', we will assume this scenario
has nothing to do with this case.
Georger, neither 377 or anyone else jumping from the rear stairs of a 727 in stable level flight is going to hit the engine exhaust. The high pressure and velocities from the engine exhaust are equalized fairly rapidly over a period of several seconds.
But the downwash and the wing tip vortices may require several minutes to completely dissipate. The downwash and vortices are the price for producing lift. And a jumper in a free fall is going to be below those things very fast.
But even a 170 knot blast of wind is going to shake up people jumping into it but it is different from the things mentioned above.
Robert99 50
Quotehttp://www.youtube.com/watch?v=Hpw8tgUoAbk
Good catch on the wing vortices hangdiver. I’m pretty sure that those jet engines aren’t counter-rotating but as everyone on this thread knows, those effects would be mitigated by the lack of asymmetric thrust therefore eliminating any concerns about a critical engine.
As Robert99 adroitly pointed out, the turbulence from extended gear at Flight 305’s airspeed would be minimal since velocity is one of those ‘Root Mean Square’ equations that I never understood (too busy being cool). I realize that the drag landing gear produces below 200 knots is minimal but my penis demands a fully retractable system like those on Beech Bonanzas and Cessna Cardinals. Having a retractable plane makes me more manly manish on the macadam. It’s just my way of scent marking others on the airfield and letting them know who the Alpha Male Silverback is in this neck of the woods. Strange how the numbers of people participating in General Aviation for fun, keeps going down, I just can’t figure it out.
Perhaps a better example of aerodynamic drag would be the ubiquitous US Postal Service and FedEx trucks that have the aerodynamics of a brick. Apparently at speeds below 25 MPH there is virtually no advantage to streamlining and these vehicles spend the vast majority of their life well below that.
Where velocity becomes critical here is with the jets that FedEx utilizes to move parcels across the country making deliveries in just one day. Much the same way the Postal Service employees gun down co-workers and fellow citizens in a fit of seething rage barely contained during the decades long fermentation triggered by the realization of a squandered life spent sorting Harriet Carter and Publisher’s Clearing House catalogs while counting down the seconds till retirement and realizing the futility of it all.
At least that’s my understanding of low velocity drag.
Farflung, I was discussing "turbulence" produced by the landing gear and not "aerodynamic drag". Retractable landing gears are very nice to have even on sailplanes.
On general aviation aircraft, fixed or retractable landing gears are mainly a function of economics only.
QuoteI realize that the drag landing gear produces below 200 knots is minimal but my penis demands a fully retractable system like those on Beech Bonanzas and Cessna Cardinals.
And for those really 'big Johnsons"....Hang gliders also have retractable gear...
hangdiver
"Mans got to know his limitations"
Harry Callahan
QuoteNot going. I live too far away plus I already have
family pouring in for the holiday.
Sorry to hear that georger...I know those pesky relates have to go somewhere.
Happy Thanksgiving to you as well.
hangdiver
"Mans got to know his limitations"
Harry Callahan
Amazon 7
QuoteQuoteI went to several skydiver websites where they
describe bailing from jets (incl the 727) and nobody
reported any problem due to engine blast etc ...
so unless Rat did something intentional to give
Cooper a 'jet blast', we will assume this scenario
has nothing to do with this case.
Georger, neither 377 or anyone else jumping from the rear stairs of a 727 in stable level flight is going to hit the engine exhaust. The high pressure and velocities from the engine exhaust are equalized fairly rapidly over a period of several seconds.
But the downwash and the wing tip vortices may require several minutes to completely dissipate. The downwash and vortices are the price for producing lift. And a jumper in a free fall is going to be below those things very fast.
But even a 170 knot blast of wind is going to shake up people jumping into it but it is different from the things mentioned above.
Can I point out.. that the jumper is also travelling at 170 Knots....
The human body though is just not as aerodynamic as the fuselage of the aircraft is. ( I have been over 300 MPH in freefall a few times... I know just a bit about this)
377 22
I thought total BS until I watched a claimant's helmet camera footage. It showed him looking down on the jet from a distance behind as he slowed down to terminal velocity and ended his climb. It looked like he was about 150 ft above the jet. It was done with a high exit speed. Could have been faked but I doubt that it was.
Anyone else heard of this or perhaps witnessed it?
377
Farflung 0
I am willing to bet that those retracts on gliders don’t have any motors, hydraulics, emergency extension systems, manual cranks, relays, switches or even doors. Probably just a Johnson (not the type your thinking of hangdiver) bar and a good pull to retract with minimal weight added, if any. A sensible and rational feature in that case.
I think some ‘sailplanes’ even come with motors, which I call an airplane. Just like categorizing seahorses that carry their young as males; nice try Mother Nature but it’s still a female seahorse. Humans have a similar subset that can be observed wandering malls across America dressed in Old Navy clothing with one of those ‘what the hell happed to me’ stares that conjure both sympathy and rage in a liberated man. I do realize these same Old Navy wearing, mall wanderers will parse what I just wrote to the sub-atomic level where they can feel secure in themselves again. One does what they have to do.
Robert99 50
QuoteQuoteQuoteI went to several skydiver websites where they
describe bailing from jets (incl the 727) and nobody
reported any problem due to engine blast etc ...
so unless Rat did something intentional to give
Cooper a 'jet blast', we will assume this scenario
has nothing to do with this case.
Georger, neither 377 or anyone else jumping from the rear stairs of a 727 in stable level flight is going to hit the engine exhaust. The high pressure and velocities from the engine exhaust are equalized fairly rapidly over a period of several seconds.
But the downwash and the wing tip vortices may require several minutes to completely dissipate. The downwash and vortices are the price for producing lift. And a jumper in a free fall is going to be below those things very fast.
But even a 170 knot blast of wind is going to shake up people jumping into it but it is different from the things mentioned above.
Can I point out.. that the jumper is also travelling at 170 Knots....
The human body though is just not as aerodynamic as the fuselage of the aircraft is. ( I have been over 300 MPH in freefall a few times... I know just a bit about this)
Amazon, You may indeed point out that a jumper in an airlplane that is doing 170 knots is also doing 170 knots (assuming he is not moving around inside the airplane).
The 170 knots means that the airplane and jumper are doing 170 knots relative to the free air stream. When the jumper separates from the aircraft, he will be in the free air stream in a few seconds and no longer going quite 170 knots with respect to the free air stream and will continue to decelerate until he has reached the "terminal velocity" for his body position, altitude, etc..
Or he may actually accelerate a bit if his terminal velocity happens to be above 170 knots for the specific conditions that he finds himself in.
On your claim to having been over 300 MPH in a free fall, would you describe the conditions of those jumps (how high were you and how was your speed determined)? Were you above 300 MPH when you jumped? Please provide this information.
In all honesty, I don't think that a human body can accelerate to 300 MPH in a free fall in the lower atmosphere, say below 10 or 15 thousand feet.
Robert99 50
QuoteLike I said Robert99, I never fully understood that ‘Root Mean Squared’ thing and simply look at drag and turbulence as ‘relatively proportional’ in my silly, stupid, decision making world. I let others parse everything down to sub-atomic levels where they can convince themselves that having a retractable plane that operates around 200 knots and 100 hours a year makes infinite sense. There is a great deal of demand for the things after all so I must be missing something here, but it’s not an extra three or four grand in insurance premiums and maintenance.
I am willing to bet that those retracts on gliders don’t have any motors, hydraulics, emergency extension systems, manual cranks, relays, switches or even doors. Probably just a Johnson (not the type your thinking of hangdiver) bar and a good pull to retract with minimal weight added, if any. A sensible and rational feature in that case.
I think some ‘sailplanes’ even come with motors, which I call an airplane. Just like categorizing seahorses that carry their young as males; nice try Mother Nature but it’s still a female seahorse. Humans have a similar subset that can be observed wandering malls across America dressed in Old Navy clothing with one of those ‘what the hell happed to me’ stares that conjure both sympathy and rage in a liberated man. I do realize these same Old Navy wearing, mall wanderers will parse what I just wrote to the sub-atomic level where they can feel secure in themselves again. One does what they have to do.
Farflung, On the retractable landing gear for most low speed general aviation aircraft, think "Ego". That is, the one who dies with the most toys wins.
The landing gear in sailplanes generally consist of a single main wheel with a small (maybe two inches in diameter) tail wheel. If the main wheel is retractable, it is usually by a mechanical system using a simple hand lever. The wheel well does have doors and they are spring closed.
In the case of high performance sailplanes (maybe a 50 to 1 lift-to-drag ratio), even lowering the drag by a pound or two, as retracting the landing gear would do, increases the performance by maybe 10 percent or more.
Robert99 50
QuoteI know this will be met with skepticism, but several WFFC jumpers reported that they climbed above the jet after exit by orienting themselves in the direction of flight and hunching their body for max lift.
I thought total BS until I watched a claimant's helmet camera footage. It showed him looking down on the jet from a distance behind as he slowed down to terminal velocity and ended his climb. It looked like he was about 150 ft above the jet. It was done with a high exit speed. Could have been faked but I doubt that it was.
Anyone else heard of this or perhaps witnessed it?
377
377, While I have never heard of this before, it might just be possible for an experienced jumper to do it. As a minimum, he would probably need to have a good visual reference to the horizon (to help maintain the proper body position) and a LOT of speed. And a "winged" jump suit would be very helpful.
Presumably, the jumper you described jumped from the stairway of a DC-9 type aircraft. If anyone tried this with a 727, they would have to go through the exhaust of the center engine and just a relatively short distance behind the engine. In other words, they probably wouldn't be around to try it a second time.
377 22
QuotewroteIn all honesty, I don't think that a human body can accelerate to 300 MPH in a free fall in the lower atmosphere, say below 10 or 15 thousand feet.
Think head down and all tucked in. I got to 185 according to my black box. Others have reportedly hit 300.
377
Robert99 50
QuoteRobt99
QuotewroteIn all honesty, I don't think that a human body can accelerate to 300 MPH in a free fall in the lower atmosphere, say below 10 or 15 thousand feet.
Think head down and all tucked in. I got to 185 according to my black box. Others have reportedly hit 300.
377
377, The speed is a function of the drag area presented by the jumper and his equipment and the total weight of jumper plus equipment.
There is a finite minimum to the drag area that a jumper can present. However, if he is to accelerate, his weight must exceed the total drag (or else he has reached his terminal velocity or is slowing down).
So in the lower atmosphere, the desired body type for such a jumper would be one that is tall, skinny, has maybe a 100 pounds of lead strapped to his head, and a helmet that has a cone top for streamling purposes.
In the upper atmosphere, say 30 or 40 thousand feet, I think that maybe 300 MPH would be possible. Of course, at 100,000+ feet, supersonic free fall is possible as demonstrated by Joe Kittinger.
Your 185 MPH agrees with everything that I have seen in the parachuting literature for head first free falls.
hangdiver
"Mans got to know his limitations"
Harry Callahan
I thought y'all would be interested in reading my latest correspondence with the FBI, specifically an email I received today from Ayn Dietrich regarding a series of questions I sent to her and Curtis Eng a week or so ago.
I am further pleased to report that Ms. Dietrich has been courteous and timely with me in all my dealings.
****************
FBI, Report from Ayn Dietrich:
Hi, Bruce—
Thanks for your patience in my responding to you. As we discussed on the phone, FBI policy restricts the release of details on a pending investigation unless necessary to further the investigation. For the most part, the questions you asked me delve into details that we cannot discuss because of this policy. For the answers I can provide, please see my comments inserted in your text below. I’d also like to make you aware of the resources that we have shared in the past, considering that information is already out there.
As you may have seen, the FBI published an updated article in 2009: http://www.fbi.gov/news/stories/2009/march/dbcooper_031709;
We recently added a “Resources” box towards the bottom, on the right-hand side—which contains links to two previous articles, a video, and the FBI Vault with released records;
In the Vault’s DB Cooper archive (http://vault.fbi.gov/D-B-Cooper), you may find the answers you are seeking.
I apologize that this isn’t exactly the assistance you were seeking, but I hope this is still helpful to some degree.
Ayn
From: Bruce Smith [mailto:BruceSmith@rainierconnect.com]
Sent: Sunday, November 06, 2011 7:27 PM
To: Dietrich, Ayn S.
Subject: Mountain News calling
Greetings Ayn Dietrich,
Here are some questions I have for you and Curtis Eng regarding DB Cooper.
I am developing a major piece on the DB Cooper case for the Mountain News http://themountainnewswa.net/category/db-cooper/, and eventual publication in my book: "The Hunt for DB Cooper – The Resurgent Investigation into America’s only Unsolved Skyjacking."
I have a number of points in my research that need clarification or confirmation; hence, I hope you can address them.
Brief responses are fine. I’m not looking for, or expecting, a “white” paper on the Cooper case. I’m just presenting the questions that are at issue for me, and if you can help me sort it out I’d be grateful
1. Confessions:
A reported 922 individuals have confessed to be being DB Cooper. Can you confirm? If this number is incorrect, can you offer an estimate of the number of confessees? Himmelsbach says “it is in the hundreds.”
Any thoughts on why so many?
AD: "I cannot get into details about this matter because it pertains to a pending investigation."
2. Money Find at Tina’s Bar
How many shards of twenty dollar bills were found at Tina’s Bar? Former PIO Dorwin Schroeder says they found “thousands” of shards and put them in plastic baggies. Gray writes in his book that there are a handful in a match box. What is the most accurate characterization in your judgment?
Also, can you share your perspective on where they were found? There is a lot of controversy on this issue. Schroeder says three-feet down in a concentrated area, but the guy on the backhoe digging up the sand, Al Fazio, says “No way!” and that they all washed-up due to tidal action and waves.
AD: "I cannot get into details about this matter because it pertains to a pending investigation."
3. Citizen Research Team
What can you tell me about the Bureau’s response to the Citizen Research Team’s finding that titanium sponge was found on DB Cooper’s tie? The CRT claims that such material could only be present in a handful of machine shops and metal research labs in 1971, and folks are clamoring to know if anyone is investigating this lead.
AD: "I will not comment specifically on its findings, but I can tell you that the team’s findings contribute meaningfully to our investigation. Although this is not an active investigation — in that the FBI is not actively looking for new evidence or witnesses — we do pursue all credible leads accordingly. Understanding everything that the physical evidence has to offer is important in any investigation, including this one."
4. Back Parachutes
The ownership of the back parachutes delivered to Cooper has recently come into question. Can you tell me the true roles of Norman Hayden and Earl Cossey in the Cooper case?
AD: "I cannot get into details about a pending investigation."
5. Other Evidence
Can you tell me the status of the eight cigarette butts left by DB Cooper? Also, what is the status of hair strands recovered from the head rest? Are either used as a source of genetic material for DNA comparison?
AD: "I cannot get into details about this matter because it pertains to a pending investigation. However, I can confirm that we do have some degree of DNA from the evidence collected on the plane."
6. Role of Richard McCoy
The role of Richard McCoy in the DB Cooper case is highly controversial in some circles. Do you think McCoy played a part in the Cooper skyjacking?
Former SAC Russ Calame shows convincingly in his book that McCoy was absent from his home in Utah on Thanksgiving, 1971, and was in Las Vegas, Nevada during the hours after the skyjacking, specifically in the environs of McCarran airport. Does any of this play a part in the Cooper case in your judgment?
AD: "I cannot get into details about a pending investigation."
7. Role of Ted E Mayfield
Former SA Ralph Himmelsbach writes in his book that Mayfield made invaluable contributions to the FBI’s investigation of DB Cooper. Can you tell me what those contributions were? Both Ralph and Ted refuse to discuss the matter with me, for unknown reasons.
AD: "I cannot get into details about a pending investigation."
8. Role of Jerry Thomas in the investigation
Former SA Ralph Himmelsbach has an extraordinarily close relationship with Jerry Thomas, and Jerry often states publicly that he assists you in the DB Cooper case. Yet, Jerry offers some wacky opinions – and in a very authoritative manner – such as that flight 305 had four flight attendants and that he knew Cooper suspect Richard McCoy in Vietnam. Can you tell me what tangible contributions Mr. Thomas has made to the case or how he has earned such an intimate position in the Bureau’s investigation?
AD: "I cannot get into details about a pending investigation."
9. Status of Ted Braden and Sheridan Peterson.
Former Vietnam Green Beret SgtM Ted Braden is widely rumored within military circles to be DB Cooper. In addition, former Marine and Vietnam refugee specialist Sheridan Peterson has been investigated by the Bureau twice in connection with the Cooper case. Can you share your perspective on these suspects, or the possibility that a former Vietnam combat commando could have been Cooper?
Similarly, what’s your perspective on the potential of former airborne troops and CIA combat contractors from the SE Asia Theater to receive the skills necessary to do the Cooper caper as part of their military experience?
AD: "I cannot get into details about a pending investigation."
10. Status of Tina Mucklow in the current investigation
Have you visited Tina Mucklow or spoken with her? Do you know why she has undergone such a profound personality change, or why she disappeared for thirty years? Has she made any contributions to the investigation in recent years?
AD: "I cannot get into details about a pending investigation."
11. Status of Lee Dormuth
What is the current status of former SA Lee Dormuth in the investigation?
AD: "I cannot get into details about a pending investigation."
12. Role of Charlie Farrell
Can you describe or characterize the Cooper investigation that SA Farrell launched in 1971? He hasn’t left any public record of his perspective on the case or evidence of his leadership style. Can you shed any light in this area?
AD: "I cannot get into details about a pending investigation."
14. Your perspective on DB Cooper?
How would you characterize your view of DB Cooper and the case? How are you conducting the case? What do you see as the key issues?
AD: "As far as a “view,” the FBI follows facts and does not make assumptions or draw conclusions. Our investigators are certain not to let their personal viewpoints get in the way of having evidence speak for itself.
"This is an open investigation but not an active one in that we are not still looking for information. That said, when tips come in to us, we assess each one and, if credible, pursue the lead accordingly."
Lastly, any chance that I could review the documents and evidence that Geoffrey Gray, Tom Kaye and others have examined?
AD: "I appreciate your interest but we are not making those materials available to the media or the public at this time."
QuoteSmith, what's wrong with you?...................................you never mentioned Duane Weber..........heheeheh
***
"Oops!"
Farflung 0
WTF?
OK, that was only one question, but if being sloppy with hyperbole while trying to save the world is a crime then I plead hunky, your honor.
So who said the Cooper hijacking was the ONLY unsolved of its species? Hmmmm….????
Let’s look at a couple others, shall we? OK, let’s shall.
On 22 February 1974 an innocent and freedom loving man named Samuel Byck was heinously and mercilessly shot to death (by his own hand) while gingerly holding a loaded pistol which was ALLEGEDLY used to kill the Co-pilot of Flight 523 and an airport security guard. As of 2011, no one has been convicted of air piracy, let alone the murder of two people associated with this flight. Why? The mystery remains UNSOLVED.
OK so that wasn’t from the Seattle area so maybe they forgot or it was not in their jurisdiction. Then how does one explain this?
On 2 June 1972, a Western Airlines flight from Seattle (naturally) was hijacked by Willy Holder (don’t judge) and Catherine Marie Kerkow. That’s right, Catherine Marie Kerkow who was last known to be residing in Cuba and just minding her own business. The FBI knows where she is, yet does nothing about this ‘solved’ hijacking? Puh-lllllleeeeeeeeasssse.
Just a lil ‘ol reality check here.
Amazon 7
Quote
I do believe there are a few in the 300mph club...it's no easy task...ask Bryan Burke...he knows...and I would guess Amazon as well...
hangdiver
I do indeed compete in Speed skydiving
I LOVE going fast... although getting unstable at over 250 MPH... hurts like hell... although you cant buy a better thrill ride when you start tumbling and spinning at those speeds
In competitions.... no lead is allowed... no pointy helmets either... although some of the guys do use some rather silly looking vinyl bobsled suits....Only standard skydiving equipment is allowed.
Jump altitude is 13500' and the measured Kilometer is from 8900' to 5500' where you pull out of the dive into a track like you cant believe... to decelerate... you get a hell of a lot of lift with the right body position and all that speed translates into some AWSUM tracks across the ground that you can VISIBLY see yourself passing cars going at freeway speeds down I-5
Usually I get big out of the track at 3500( go to a normal flat stable position out of the track once I have bled off MOST of the speed.. and deploy at 2500' or so.
OK. Im sorry.
Lets just let Blevins, Airtwardo, and Class Clown and
JT and you set the agenda here. And not post
anything else?
So Robert99, what will Blevins and his mother be
eating on Thanksgiving Day? Give us the inside
story! Did you know Blevins wont be attending the
Ariel Party or the Symposium - did you get that?
Blevins. Post it again. Some may have missed it.
Jet engines on airplanes dont matter nohow -
yepper! YEEEEEEEEEEEEEEEEEEEEEHAW!
Dead air zone - dead air zone!
8 days and counting.
Okay smarty pants, I'll tell you what the term "dead air" means in this instance.
But first, where did you get that beautiful picture of a two-engine "727" in your attachment? Do you think a three-engine "727" would have a more pronounced downwash and trailing wing tip vortices, other things being equal?
In 377's previous posts about jumping from a DC-9 stairway, he stated that for a few feet after leaving the fuselage exit the air was relatively calm. Then things got extremely turbulent as he hit the free stream air flow. A few seconds after that, 377 would be clear of the downwash and turbulence behind the aircraft and the rest of the freefall would be "normal" (at least after he slowed down to his personal terminal velocity).
The term "dead air" refers to that first few feet of air flow that 377 described. Hominoid and I have also pointed out that the same phenomena of "dead air" can be observed on any car or truck on the free way during rainy weather. That is the behavior of the air that you can see around the rear bumper area.
On the matter of jet engines on airplanes, they do matter if you are interested in getting from Point A to Point B in a reasonable time. If you are not interested in doing that, they don't matter (you just have a sailplane).
I'll leave the other questions to anyone who knows what the answers might be.
Share this post
Link to post
Share on other sites