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n1_spindown
30th Jan 2010, 06:25
does anybody know much about solar cosmic radiation? I know pilots have much more exposure to it... most of the research I found on the web is more than 8 years old...I know trans polar and higher altitudes really increase the exposure levels..

Loose rivets
1st Feb 2010, 07:52
There's an AME just north of LGW that was involved in a study. Can't remember his name, but others might.

777AV8R
4th Feb 2010, 03:07
The exposure rate is much LESS than you think. I wrote a White paper on the subject a few years ago. The FAA has a real-time website that you can access and get your exposure rate for any flight.

In my study, you would have to cross the North Pacific over 245 times in order to bring you up to the 5mSV rate. The real danger lies in a Solar Flare event. These are unpredictable and can cause some problems.

changer
17th Dec 2010, 07:19
perhaps someone can answer my stupid question:

Are you less exposed to cosmic radiation flying at night vs daytime?

wiggy
17th Dec 2010, 11:20
If you mean cosmic radiation as in Intergalactic Cosmic Radiation, then the answer is that day or night is irrelevant.

As 777AV8R has pointed out the really significant stuff is the output from Solar Flares, and as far as I'm aware as a first approximation day/night makes little if any difference. Altitude and magnetic latitude are much more important factors.

AvMed.IN
17th Dec 2010, 13:59
Prof Michael Bagshaw who had done some outstanding work on Concorde, had discussed this issue elsewhere at a symposium (full transcript of the symposium at Stress, the Business Traveler and Corporate Health: Proceedings (http://www-hsd.worldbank.org/symposium/427-3-bagshaw.htm) )
"The Concorde flies up to 60,000 feet and gets a higher dose of radiation than a subsonic airplane. So for the last 25 years, we've been monitoring cosmic radiation exposure on the Concorde.
We also monitor cosmic radiation exposure on our long-haul aircraft. The International Commission on Radiological Protection recommended dose limit for a worker, is 20 milliSieverts per annum.
If you take the radiological protection practice of taking three-tenths of the occupational exposure as being the limit for deciding whether a worker is a controlled worker or not, that works out at six milliSieverts per annum.
Our work shows that the average Concorde flight crew are getting about four milliSieverts per year. Theoretically, they can go up to six, although we've got no crew members who do reach six. Long-haul crew flying 747s on very long range—over the Poles, over the Northern latitudes— get on average between four to five, with a maximum of five milliSieverts, and short-haul crew operating in Europe are getting about three milliSieverts per annum.
So what we're finding is that cosmic radiation exposure is well below the International Commission on Radiological Protection standard, and our epidemiological studies show that our long-haul crew on average live about five years longer than a matched population.".

He had also published an article "British Airways Measurement Of Cosmic Radiation Exposure On Concorde Supersonic Transport. Bagshaw, Michael, Health Physics: November 2000 - Volume 79 - Issue 5 - pp 545-546"

Considering they monitored cosmic radiation for over 25 years, even if this report is of circa 2000 vintage, the findings hold true.
Hope this answers your query!

Aer Doctor
18th Dec 2010, 04:40
check out this link for information on radiations to civil pilots

http://pilots-medical.com/Radiationinpilots.htm

no-hoper
18th Dec 2010, 10:26
Are there any informations about radiation on aircraft engines ?Some of the old engineers trying to stay away from jobs in the fan area...

V1
20th Dec 2010, 20:19
There was a UK Cosmic Radiation Working Group set up back in about 2002 which was instigated by an AME at the CAA and comprised representatives from the CAA, Virgin, BALPA, DFT (I think), and various Scientists including a couple from the Rutherford Appleton Laboratory, and a few others.

As it is impracticable to measure each pilots own ACTUAL radiation exposure the aim I believe was to examine the various mathematical models that had been developed and to validate these with a view to using the figures in rostering packages such as AIMS to be able to account for the cumulative total a pilot has received.

I know Virgin carried various test boxes on board its aircraft to get some actual data to validate the mathematical models, and I remember some reports being made back to the UK Flight Safety Committee, so they may be a source.

The only startling fact I can recall is that your exposure at 40,000 ft is double that at 30,000 ft - & generally long polar flights will expose you to way more than short European sectors.