Kobuk Airport to Bettles Airport OBU → BTT
126 nautical miles (145 statute miles) east on a straight line, true course 087°, about 076° magnetic at the departure end (variation 11E). At 120 knots that is 55 min at the quickest height in today's winds (34,000 ft, a 17-knot tailwind), arriving about 4:44 pm AKDT (00:44 UTC). Right now BTT is marginal VFR, wind variable at 6 knots. For planning, not a briefing: the legal preflight briefing comes from Flight Service (1-800-WX-BRIEF) or the FAA's own tools. Airlines fly this pair: 15 flights in the DOT's last twelve reported months, the route's page.
The route the straight line, the warnings crossed, restrictions, pilot reports and the airports along the way · click a mark for its words
Green, blue, red and purple airport dots are the flying conditions reported there now (VFR, marginal VFR, IFR, low IFR); grey means no report. Red areas are SIGMETs, orange areas AIRMETs, hatched red areas temporary flight restrictions. Map tiles: OpenFreeMap, data © OpenStreetMap contributors.
Warnings the route crosses SIGMETs and AIRMETs whose area the line passes through or comes within 25 nm of
No SIGMET or AIRMET covers any part of this route right now.
A SIGMET warns of weather hazardous to all aircraft; an AIRMET of weather that matters to small aircraft and to flying without instruments. "From 60 to 180 nm out" is measured along the route from OBU.
Pilot reports along the route within 50 nm of the line, last three hours, the serious ones first
Not fetched just now.
Winds aloft along the route, and the time en route the forecast for use 20:00–03:00 UTC · at 120 knots true airspeed
The eastbound cruising heights for this course (VFR: odd thousands plus 500 ft; above 18,000 ft the forecast levels), with the wind averaged along the line from the 2 forecast points nearest it (AFM, BTT). A plus sign is a headwind, a minus sign a tailwind.
| Height | Average wind | Head- or tailwind | Temperature | Ground speed | Time en route | Arrival |
|---|---|---|---|---|---|---|
| 3,500 ft | 170° at 3 kt | 0 | 120 kt | 1 h 03 min | 4:52 pm AKDT (00:52 UTC) | |
| 5,500 ft | 180° at 2 kt | 0 | 120 kt | 1 h 03 min | 4:52 pm AKDT (00:52 UTC) | |
| 7,500 ft | 220° at 4 kt | −3 kt | -9 °C | 123 kt | 1 h 01 min | 4:50 pm AKDT (00:50 UTC) |
| 9,500 ft | 230° at 7 kt | −6 kt | -13 °C | 126 kt | 1 h | 4:49 pm AKDT (00:49 UTC) |
| 11,500 ft | 230° at 10 kt | −8 kt | -17 °C | 128 kt | 59 min | 4:48 pm AKDT (00:48 UTC) |
| 13,500 ft | 230° at 12 kt | −10 kt | -21 °C | 130 kt | 58 min | 4:47 pm AKDT (00:47 UTC) |
| 15,500 ft | 230° at 15 kt | −12 kt | -25 °C | 132 kt | 57 min | 4:46 pm AKDT (00:46 UTC) |
| 17,500 ft | 230° at 18 kt | −14 kt | -29 °C | 134 kt | 56 min | 4:45 pm AKDT (00:45 UTC) |
| 18,000 ft FL180 | 230° at 19 kt | −15 kt | -30 °C | 135 kt | 56 min | 4:45 pm AKDT (00:45 UTC) |
| 24,000 ft FL240 | 210° at 21 kt | −10 kt | -43 °C | 130 kt | 58 min | 4:47 pm AKDT (00:47 UTC) |
| 30,000 ft FL300 | 210° at 21 kt | −12 kt | -55 °C | 132 kt | 57 min | 4:46 pm AKDT (00:46 UTC) |
| 34,000 ft FL340 | 230° at 22 kt | −17 kt | -53 °C | 137 kt | 55 min | 4:44 pm AKDT (00:44 UTC) |
| 39,000 ft FL390 | 220° at 25 kt | −17 kt | -48 °C | 137 kt | 55 min | 4:44 pm AKDT (00:44 UTC) |
Based on data from the 11th at 18:00 UTC; valid on the 12th at 00:00 UTC for use 20:00 to 03:00 UTC; temperatures above 24,000 ft are below zero. Heights are above sea level; a height is left out when the forecast has no wind for it over most of the line (the ground is higher). Ground speed is the airspeed less the headwind; the time en route is for the straight line and ignores climb, descent and routing around weather.
The forecast points as issued
| Point | From | 3,000 | 6,000 | 9,000 | 12,000 | 18,000 | 24,000 | 30,000 | 34,000 | 39,000 |
|---|---|---|---|---|---|---|---|---|---|---|
| AFM | used from 0 nm out; 48 nm from the line | 170/7 | 180/6 -7° | 220/5 -12° | 240/6 -19° | 200/13 -32° | 200/17 -43° | 220/18 -54° | 230/21 -54° | 230/21 -49° |
| BTT | used from 49 nm out; 53 nm from the line | L/V | L/V -6° | 240/8 -12° | 230/13 -18° | 240/24 -29° | 210/24 -43° | 210/23 -55° | 230/22 -53° | 220/27 -48° |
The weather now: both ends and the airports along the way public airports with a weather report within 25 nm of the line, one for each stretch
| Airport | Where | Conditions | Wind | Visibility | Ceiling | Elevation | Reported |
|---|---|---|---|---|---|---|---|
| OBU Kobuk, AK | departure | no report just now | 142 ft | ||||
| 6A8 Allakaket, AK | 97 nm out, 23 nm south of the line | no report just now | 441 ft | ||||
| BTT Bettles, AK | destination | marginal VFR Sky: a few clouds at 1,200 feet, a broken layer at 2,500 feet, overcast at 5,000 feet | variable at 6 knots | 7 mi | 2,500 ft | 647 ft | 2:53 pm AKDT (22:53 UTC) |
The highest airport on this list sits at 647 ft; the ground between airports is higher still. Check the sectional chart for the terrain and the minimum safe heights along the line.
At BTT when you get there the forecast at the estimated arrival, 4:44 pm AKDT (00:44 UTC)
Wind from the north-northeast at 4 knots, visibility 6 miles, mist, showers nearby, scattered clouds at 1,500 feet, a broken layer at 2,500 feet and more above marginal VFR
The whole forecast for BTT
- From Sun 4:00 pm AKDT (00:00 UTC): wind from the north-northeast at 4 knots, visibility 6 miles, mist, showers nearby, scattered clouds at 1,500 feet, a broken layer at 2,500 feet and more above
- From Mon 2:00 am AKDT (10:00 UTC): wind from the south-southeast at 2 knots, visibility 2 miles, light snow showers, overcast at 700 feet
Temporary flight restrictions on the line or within 25 nm of it
No temporary flight restriction on or near this route right now.
Daylight
Sunset at OBU 7:09 pm AKDT (03:09 UTC), at BTT 6:48 pm AKDT (02:48 UTC) (civil twilight ends 7:42 pm AKDT (03:42 UTC)).
Each restriction opens the FAA's own page with the exact area, heights and times. Ordinary notices to air missions (closed runways, lights out) are not shown: the FAA's notice search is not open to sites like this one at this time.
Radar and forecast charts for the regions crossed government pictures, the latest each time the page loads
Sources: the Aviation Weather Center's data service (SIGMETs, AIRMETs, graphical AIRMETs, pilot reports, winds and temperatures aloft, observations and terminal forecasts), the National Weather Service radar, the Weather Prediction Center's charts, the FAA's temporary flight restriction list and shapes, and the FAA's airport file for the positions, elevations and magnetic variation. Fetched when the page is viewed and kept a few minutes. Each leg is the straight line between its two airports; airways, terrain and airspace are not considered. The airports in detail: Kobuk Airport, Bettles Airport.