rickair7777

I can only imagine. Step 280/300/ 320.

Sliceback

Concerned about radiation? Fly n/b to the southern U.S., short legs, with as many legs per month as possible. :45 legs out of CLT and MIA? That's winning the radiation game. JFK-DFW and JFK- Paris, 700 hrs a year, FL340 to and from DFW and FL320 to and from Paris? DFW flight over 700 hrs is 4% less radiation (2.5 mSv vs 2.6 mSv to Paris) (using August 2023 radiation). The 787 would be 4.3 mSv or 61% more. APA's aeromedical committee has a chart showing the cumulative death risk from exposure to inflight radiation.

Sliceback

https://jag.cami.jccbi.gov/

Keep in mind you're generic cancer risk is approx. 45% (+/-) and your odds of dying from cancer are approx. 23% (white male).

From the previous post flying a 787 vs a 321XLR might had 17 mSv's of exposure over 10 years. Bump your lifetime exposure from 130 mSv's to 150 mSv's? Given 130 mSv's would already see 437 deaths the 787 pilot who flew the 787 to Europe instead of the 321XLR would be looking at 438 deaths.

Lifetime mSv death risk - 50 mSv - 1:5000, 75 mSv - 1:3200, 100 mSv - 1:2500, 125 mSv - 1:2000, 150 mSv - 1:1700, 175 mSv - 1:1400. Data presented in 10 mSv increments. I adjusted to nearest 100 when converting to 75/125/175 mSv exposure death rates.

Sliceback

321 OPT ALT is approx. 510 (520) minus weight in thousands. 210,000 lbs TOC? 510-210 = FL300. 520-310 = FL310. That's a =/- SWAG. No wind adjusted. 321XLR range will be approx. 757 3900 nm (pre winglet) + 500-600 nm. Subtract approx. 700 miles for winter winds and you have an range estimate for the possible city pairs to fly back to the U.S.

rickair7777

I have physicists in the family, as a casual exercise we reviewed the radiation impact on flight crew. What you're saying looks right.

High altitudes, latitudes, and obviously more flight time increases your exposure and risk. The ultimate net risk is statistically detectable but just barely. I wouldn't necessarily bid-avoid CDG if you enjoy the layovers.

Then we looked at solar flares

Let's just say I've been known to feel under the weather when a big flare is going down.

Name User

Higher is quieter on all fronts, which I much prefer. I like to climb / follow FMS+ because I like our airline to be as profitable as it can. I understand many don't share that viewpoint, and apparently the cool kids DGAF, but I will never understand the "don't care" aspect of being efficient.

Of course, ride comes first but all things being equal, potential savings are $500-$1000 per leg on the longer ones. Disptach software plans around WSI turb FPGs but oftentimes they are hours outdated and conditions change, allowing you to climb 8k - 10k and save boatloads of gas vs planned. Plus practically speaking, why waste a resource? It's just sloppy. IMO

Sliceback

I compared 777 flights from JFK, ORD, DFW and LAX to NRT, B.A. and LHR. Guess which city pair was the worst*? The flights were all within 10% of each other. The 777-200 was the worst until the 787 came on property...

My personal favorite was the 'legal expert' (could testify as an expert in court for law suits) that wouldn't fly above FL340 due to radiation...even in S.A. But they'd fly that high going to Europe. There is NO city pair in S.A. flown at FL410 that has anything like the radition expousre going over to Europe. FL410 MIA-EZE is .027 mSv. MIA-Paris is .027 mSv at FL320. MIA-Paris at FL340 is .031 mSv. MIA-EZE at FL 340 is .018 mSv. They'd fly around with a personal max altitude of FL340 "due to radiation" but flying to Europe they'd get more radiation than they would flying to EZE at FL410...and they normally flew to Europe. So they're absorbing approx. 72% more radiation than they'd accept going 'Deep South'. Hey...but they're an 'expert' in the eyes of the court. :-/ Guys hated it. Bouncing around at FL330, when FL410 was available, can make for a VERY long night crossing the Amazon.

JFK-LHR was the worst. Light so they'd have the highest average cruise altitude and were closest to the magnetic north pole. I would have guess ORD-NRT was the worst. Either DFW or LAX to NRT was the lowest...but so many pilots/FA's worried about "how long we're in the radiation". It was, on average, at a lower latitude and lower altitude. "I like JFK-LHR because you're not in the air as long..." Okay, that's not what the science shows.

Sliceback

Bingo.

Decades ago I flew with a guy that did transcons at FL280 in a 757/767 for radiation. We'd get to top of climb and he'd say "see, we're already saving gas." No Xx, it's because we're 10,000' lower than planned. We'll burn more per hour and eventually land with less. Sure enough we land with less... "that's because we had to deviate around those thunderstorms." Uh, seriously? You think a 30 degree turn to offset 20-30 miles for 100 miles burned 2,000 lbs extra PLUS the 1,000 lbs you 'saved' in the climb? The actual time of the entire divert would add about 1 minute...at roughly 150-200 lbs per minute.

Name User

You can't explain anything to them, they already know it all. Even using pictures and simple math like a² + b² = c²

But they'll rage talk about their buddies profit sharing checks at other airlines for an entire four day

m78fl370

Lol, probably not. Taking off at 206k, you ain’t getting much above 300, 310 for a looong time….