Marlborough, Connecticut · field elev 540 ft
Density Altitude at Salmon River Airfield (9B8)
Salmon River Airfield sits at 540 ft, and even a typical July afternoon (81 °F) only lifts density altitude to about 2,059 ft — heat still trims performance, but the field rarely turns high-and-hot.
Typical density altitude by month
| Month | Avg temp °F | DA at avg temp | Afternoon high °F | DA on a typical afternoon |
|---|---|---|---|---|
| January | 26.9 | −1,504 ft | 35.0 | −935 ft |
| February | 28.8 | −1,369 ft | 37.2 | −783 ft |
| March | 36.3 | −845 ft | 44.8 | −262 ft |
| April | 47.5 | −80 ft | 57.0 | 553 ft |
| May | 57.7 | 599 ft | 67.6 | 1,243 ft |
| June | 66.3 | 1,159 ft | 75.6 | 1,752 ft |
| July | 71.7 | 1,505 ft | 80.5 | 2,059 ft |
| August | 70.0 | 1,397 ft | 79.1 | 1,972 ft |
| September | 63.4 | 972 ft | 72.7 | 1,569 ft |
| October | 52.1 | 229 ft | 61.3 | 835 ft |
| November | 42.1 | −446 ft | 50.3 | 109 ft |
| December | 32.7 | −1,095 ft | 40.1 | −583 ft |
▲ above 5,000 ft · ⚠ above 8,000 ft. These are planning references at standard pressure and dry air — afternoon humidity and low pressure both push the real number higher. Run today's values below.
Run today’s numbers for 9B8
DENSITY ALTITUDE
Field elevation 540 ft — the air behaves like 2,090 ft.
- PRESSURE ALT
- 541 ft
- ISA DEVIATION
- —
- RULE-OF-THUMB DA
- —
- AIR DENSITY INDEX
- —
- AIR DENSITY
- —
- WATER · GRAINS/LB
- —
For training and reference · verify with official sources and your POH before flight · no tool on this site renders a go / no-go judgment
Nearby Connecticut fields
- 42B — Goodspeed
East Haddam · elev 9 ft
- KSNC — Chester
Chester · elev 416 ft
- KHFD — Hartford-Brainard
Hartford · elev 18 ft
- KIJD — Windham
Willimantic · elev 246 ft
- KMMK — Meriden Markham Municipal
Meriden · elev 103 ft
- 4B8 — Robertson Field
Plainville · elev 202 ft
- 7B9 — Ellington
Ellington · elev 253 ft
- 7B6 — Skylark Airpark
Warehouse Point · elev 120 ft
Frequently asked questions
How high does density altitude get at 9B8 in summer?
On a typical July afternoon — around 81 °F at the nearest NOAA normals station — density altitude at Salmon River Airfield reaches roughly 2,059 ft at standard pressure. Hotter-than-normal days, low pressure, and humidity all push it higher, so run the day's actual numbers before flying.
What is the density altitude at 9B8 on an average day?
It swings with the seasons: from roughly −1,504 ft at the coldest month's average temperature to about 1,505 ft at the warmest month's — all from a constant field elevation of 540 ft. The month-by-month table above carries the full year.
What is the field elevation of Salmon River Airfield?
540 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is 9B8 (FAA), in Marlborough, Connecticut.