Cosmic radiation on flights from Los Angeles (LAX) to Honolulu, Oahu (HNL)

Reverse: Honolulu, Oahu → Los Angeles

A flight from Los Angeles International Airport to Daniel K. Inouye International Airport at 35,000 ft, about 5 h 25 min in the air, receives about 0.0119 mSv (11.9 µSv) of cosmic radiation: about 12% of a chest X-ray. That is the FAA's CARI-7 model run for this route with the solar conditions of August 2026.

Updated · solar conditions of August 2026

Dose
11.9 µSv0.0119 mSv
Time in the air
5 h 25 minestimated
Dose rate
2.2 µSv/haverage, 35,000 ft
Chest X‑rays
0.12at 0.1 mSv each

Key facts: LAX → HNL

Dose, standard flight0.0119 mSv (11.9 µSv)
Time in the air5 h 25 min, estimated from distance and prevailing winds
Cruise altitude35,000 ft
Average dose rate2.2 µSv/h
Great-circle distance4,108 km (2,553 mi)
Furthest from the equator33.9°N
Solar conditionsAugust 2026

The standard flight is CARI-7, the FAA Civil Aerospace Medical Institute's model, run on the dev machine for this route: 35,000 ft, 5 h 25 min in the air (climb 25 min, cruise 283 min, descent 17 min), effective dose per ICRP Publication 103. How it's calculated.

LAXHNL
Great-circle route, shaded from 1.6 µSv/h to 2.9 µSv/h. Shading is modelled from the monthly dose-rate grid; totals are CARI-7.

How the sun changes the dose on LAX → HNL

The sun's 11-year cycle moves this number. With the same 5 h 25 min at 35,000 ft, the flight would have received 0.013 mSv in October 2018, when the sun was quiet and more galactic cosmic rays reached the atmosphere, and 0.0107 mSv in January 2026, near solar maximum: 22% more at the quiet end. In August 2026 it is 0.0119 mSv.

Dose for this flight at 35,000 ft, quarterly
0 µSv5 µSv10 µSv15 µSv20162018202020222024202613 µSv10.7 µSv11.9 µSv
0 µSv5 µSv10 µSv15 µSv20162020202413 µSv10.7 µSv11.9 µSv
The numbers behind the chart
MonthDoseDose
January 201612.4 µSv0.0124 mSv
April 201612.6 µSv0.0126 mSv
July 201612.5 µSv0.0125 mSv
October 201612.7 µSv0.0127 mSv
January 201712.8 µSv0.0127 mSv
April 201712.9 µSv0.0129 mSv
July 201712.8 µSv0.0128 mSv
October 201712.7 µSv0.0127 mSv
January 201812.8 µSv0.0128 mSv
April 201812.9 µSv0.0129 mSv
July 201812.9 µSv0.0129 mSv
October 201813 µSv0.013 mSv
January 201912.8 µSv0.0128 mSv
April 201913 µSv0.013 mSv
July 201912.9 µSv0.0129 mSv
October 201913 µSv0.013 mSv
January 202013 µSv0.013 mSv
April 202013 µSv0.013 mSv
July 202013 µSv0.013 mSv
October 202013 µSv0.013 mSv
January 202112.8 µSv0.0128 mSv
April 202113 µSv0.013 mSv
July 202112.9 µSv0.0129 mSv
October 202112.9 µSv0.0129 mSv
January 202212.8 µSv0.0128 mSv
April 202212.8 µSv0.0127 mSv
July 202212.3 µSv0.0123 mSv
October 202212.5 µSv0.0125 mSv
January 202312 µSv0.012 mSv
April 202312.1 µSv0.0121 mSv
July 202311.8 µSv0.0118 mSv
October 202311.8 µSv0.0118 mSv
January 202411.5 µSv0.0115 mSv
April 202411.7 µSv0.0117 mSv
July 202411.7 µSv0.0117 mSv
October 202411 µSv0.011 mSv
January 202511.2 µSv0.0112 mSv
April 202511.2 µSv0.0112 mSv
July 202511.1 µSv0.0111 mSv
October 202511.3 µSv0.0113 mSv
January 202610.7 µSv0.0107 mSv
April 202611.4 µSv0.0114 mSv
July 202611.7 µSv0.0117 mSv
August 202611.9 µSv0.0119 mSv

How cruise altitude changes the dose

Flown at 31,000 ft instead, the same flight would receive 0.00893 mSv, 25% less than at 35,000 ft; at 41,000 ft it would receive 0.0163 mSv, 37% more. Same route, same time in the air, same month: only the air overhead changes.

Dose for this flight by cruise altitude, August 2026
  • 31,000 ft8.93 µSv
  • 33,000 ft10.4 µSv
  • 35,000 ft11.9 µSv
  • 37,000 ft13.5 µSv
  • 39,000 ft15 µSv
  • 41,000 ft16.3 µSv

Try it: change the altitude and the month

Every combination is its own CARI-7 run for LAX → HNL, with the same 5 h 25 min in the air. It is still a standard flight, not yours: the app calculates your exact flight.

Every combination as a table (µSv)
AltitudeJan 2016Jan 2017Jan 2018Jan 2019Jan 2020Jan 2021Jan 2022Jan 2023Jan 2024Jan 2025Jan 2026Aug 2026
31,000 ft9.299.549.599.569.719.599.589.018.628.3788.93
33,000 ft10.811.111.211.111.311.211.210.5109.759.3210.4
35,000 ft12.412.812.812.81312.812.81211.511.210.711.9
37,000 ft1414.414.514.414.614.514.413.61312.612.113.5
39,000 ft15.61616.11616.316.116.115.114.41413.415
41,000 ft1717.517.617.517.817.617.616.515.815.314.616.3

The return flight: HNL → LAX

HNL → LAX receives 0.0105 mSv at 35,000 ft, 12% less than LAX → HNL, over about 4 h 47 min in the air against 5 h 25 min. The return is 38 min shorter: its track runs with the prevailing westerly winds at cruise altitude. Cosmic radiation builds up with every minute aloft, so the longer direction collects more of it along the same path.

Dose for each direction, standard flight
  • LAX → HNL11.9 µSv
  • HNL → LAX10.5 µSv

Cosmic radiation on Honolulu, Oahu → Los Angeles flights

What 11.9 µSv compares with

Compared withIts doseThis flight is
Chest X-Ray0.1 mSvabout 12% of a chest X-ray
Dental X-Ray0.005 mSvabout 2.4 dental X-rays
Background Radiation (Daily)0.008 mSvabout a day's natural background radiation
Mammogram0.4 mSvabout 3% of a mammogram
Head CT Scan2 mSvabout 1% of a head CT scan
Eating a Banana0.0001 mSvabout 119 bananas

The comparison values are the ones the FlightDose app uses.

Why your flight will differ

  • Altitude. Flown at 31,000 ft instead, the same flight would receive 0.00893 mSv, 25% less than at 35,000 ft; at 41,000 ft it would receive 0.0163 mSv, 37% more. Same route, same time in the air, same month: only the air overhead changes.
  • Time in the air. Every extra 30 minutes on this route adds about 1.1 µSv. Headwinds, holding and routing change it by tens of minutes on a long flight.
  • The month. The sun's 11-year cycle swings this route's dose by about 22% between quiet and active years.
  • The track. Airlines fly tracks that bend with the jet stream, not the exact great circle; a track further from the equator collects more.
  • Solar storms. A rare solar radiation storm can add to the dose for hours; CARI-7's monthly figures don't include one.

FlightDose calculates your exact flight.

Your date, your altitude, your time in the air, with live space weather, and a running total against the limits that matter to you.

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