Eyewitness observation of black rain in the Christmas Island Megaton Test, Grapple Y

7/28/2019 Eyewitness observation of black rain in the Christmas Island Megaton Test, Grapple Y

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in the air impacting the Tropopause and freezing into a flat layer of alto stratus cloud

against the bottom of the Tropopause.

It was this thin layer of cloud that enabled me to see how the ball lifted the

tropopause, 3 times, before it breached through.

The cloud itself spread across the bottom of the stratosphere to a diameter of 60nautical miles, when it seemed to stop

spreading. At this stage the cloud was black, and the only movement I observed was

the roiling at the edges. I would

suggest that the reason the cloud stopped spreading, the venting into the stratosphere

was acting live a safety valve. The

atmospheric cloud carried on roiling while there was still energy within the cloud.

Roiling stopped about H+ 30 minutes,

then the sampling started.

We started the initial sampling lower down through the stem. A shallow cut to check

cloud temperature, and for oxygenin the cloud to sustain the engines. The roiling of the cloud sucked in oxygen for the

engines, plus a lot of water.

Regarding ultra fine dust from the cloud, there was an orange haze left behind by the

plasma. Like a fingerprint, bit

I don't know what happened to it.

Hope I've answered some of your questions.

Regards

Joe

From: Dai Williams To: lorenzo ; Chris Busby Sent: Friday, January 6, 2012 9:31 PMSubject: Re: Erics Radiation Readings

Dear Joe and Chris

Thank you very much Joe for this latest and previous reports Joe.I have been discussing these with Chris this week who has additional FOI

or similar data. Chris is doing further analysis of radiation sourcesso I have copied him in this reply. It would be helpful if you could includehim in your data and assessments.

One aspect that interests me is the extent of the cloud for each test, plusspread and drift relative to ground zero. The NOAA data gives potentialdrift at various altitudes, though limited at the higher levels.

Most of the published photographs appear to be taken in the first 10-20minutes - classic shape nuclear clouds rather like tight cap mushrooms.Your paintings and traverse timings suggest later evolution more like a


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toadstool or very flat cap mushroom.

Do you have any other images of the clouds at H+60 to H+120 or H+180minutes? Or could you sketch some now? Sounds like they mostly flattenedout at the tropause.

And were they largely circular, or very elongated? Curious to know howmuch dispersal was radial (in all directions) from the initial blast andfollowing updraft through the stem, versus elongated by prevailing winds.

The extent and duration of the cloud is relevant to rain reports at groundlevel. At high altitudes (temperatures down to -70C from Met data?) thismust have started as freezing rain down to freezing level (typically4-5000 metres). What was the stem and cloud made of? - ice crystalsperhaps? The highest natural met equivalent might be CBs - cumulo nimbuspeaks of thunder clouds, usually max to 10,000 metres. Or were there sometemperature paradoxes in the clouds? Was airframe icing a problem?

Incidentally what altitudes were the Shackletons typically operating at?Another question might be the extent of non-visible fallout under the cloudand around the stems - ultrafine dust rather than water vapour.

As usual the hunt goes on to identify the potential dispersion, depositionand physical properties of fallout. Your original tasks were awesome Joe.Your clarity now many years later is amazing.

I hope we can be in contact again over the weekend. Chris is working ona deadline for next Wednesday.

YoursDai

.

----- Original Message -----From:lorenzoTo:Dennis HaydenCc:Stephen Evans ; DAI WILLIAMSSent: Friday, January 06, 2012 9:08 PMSubject: Erics Radiation Readings

Dennis

In response to your recent e-mail, are you and Shirley aware that I have all of Eric

Denson's radiation readings?

I logged down all the radiation readings transmitted during Grapple Yankee. It was

part of my job.

Sampling aircraft had to broadcast the readings every 15 seconds. In case they hit a

'hot' spot, and melted away.

Back at Grapple Operations, the sampling aircraft were being tracked by radar, while

they were conductingtheir sampling runs. If they melted away - the blips would have disappeared.
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I'm sure that the radar traces were also being filmed. Over a year ago I placed a FOI

request for the

voice recordings of the radiation doses that had been broadcast - to be told that they

did not exist.

The readings, together with photocopies of my original Navigation Log. Where I

recorded all the readings.

Were sent to Stephen at Rosenblatt, two years ago. Together with a bunch of other

materials pertinent to

the tests.

After 50 years my original Navigation Log is difficult to read. The lead pencil writing

is falling off the paper.

So I made a transcript of all the radiation readings I recorded after the detonation of

Grapple Yankee. Eric's

readings, broadcast by my best pal Dickie Kingdon (Eric's Navigator) are attached.This is just one page of

three that I made, but it is Germaine as it focuses on Eric's Sniff Two mission.

You need a translator to decipher this 'gob-baldy goop'. So here goes:

HT = Height in 100 foot intervals

TIC = Time in Cloud

H+ = Minutes after bomb detonation

R = ROMEO A Geiger counter installed in the aircraft, that recorded the

'gamma' radiation dose rate per hour.

C = CHARLIE A cumulative radiation measuring meter that 'should' have

provided the cumulative 'gamma' dose. (Some hope!)

S = SALMON A Gas Sampling meter. When it is maxed out at 50+, the

'gamma' dose rate exceeds 200 Roentgen per hour.

These readings were broadcast every 15 seconds, so you can measure how much time

an aircraft was in the cloud.

Eric made two cuts through the Yankee cloud. The first at H+ 68 minutes 10 seconds,

at a height of 51,000 feet. The second at

H+ 79 minutes 30 seconds at an incredible altitude of 53,500 feet. He would havebeen flying with his finger nails. No one else

got near that height. Which may explain why he got the highest dose of the day. (See

the radiation readings).

He must have been flying a few feet away from the bottom of the tropopause, where

the radiation concentration would have been

at the highest level. We did not have pressure suits. It would have required major

aircraft modifications to have them installed.

Without them, we should not have climbed above 47,000 feet. If the cabin

depressurized, we would have 'boiled' to death.


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Unfortunately, there were many problems with all the radiation instruments. They did

not work well, and certainly were not

talking to each other.

Take the first run. The SALMON instrument was asleep and recorded nothing. You

will notice the ROMEO readings buildingup, then falling off right at the end just before the cloud was exited. NOTE ALSO

THE FINAL CHARLIE READING OF 9.9 Roentgen.

With the second cut, the CHARLIE meter has re-zeroed, and starts off at 4.3

Roentgen. What happened to the 5.6 Roentgen that dropped off??????

These don't get counted in at the FINAL CHARLIE count. Also, throughout the entire

run the SALMON meter is recording 50+, which is

indicative of a dose rate in excess of 200 Roentgen. However the maximum ROMEO

reading is only 20. Perhaps ROMEO was busted on

the first run through the cloud.

On the second run, SALMON indicates a minimum Roentgen level of 200 gamma

Roentgens per hour. It could have been higher - 300 or even

400 Roentgen per hour. Assuming it stayed at 200 Roentgen - then 5 minutes in the

cloud would have yielded a cumulative dose of 17 Roentgen.

Plus the 10 Roentgen received on the first run, yields a bare minimum of 27

Roentgen. More likely he was way up in the 40 Roentgen levels.

Last August, I think I demonstrated how useless Film Badges are in recording

radiation levels. This should serve to show that the aircraft

instrumentation were equally as bad. The same things occur with Sniff One and Sniff

Four, instruments going to sleep and not communicating

with each other.

Hope this gives Shirley something she can use to compare to the 'fictional' readings

being generated by AWE and MoD.

Best to all

Joe

Eyewitness observation of black rain in the Christmas Island Megaton Test, Grapple Y

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