NASA ER-2 High-Altitude Science Flight & Atmospheric Mission Planner

Flight Controls

STRATOSPHERE

Cruising Altitude 65,000 ft (19.8 km)

10,000' (FL100) 36,000' (Tropopause) 72,000' (Max)

Command Mach 0.715 M

Mission Scenarios

Active Scientific Instrument Suite

AVIRIS-4 Hyperspectral

Measures solar reflected radiance from 380 to 2510 nm in 224 contiguous spectral bands. Used for mineral mapping, canopy chemistry, and snow hydrology.

Field of view: 34° total | IFOV: 1.0 mrad | Cross-track scan

PLATFORM:NASA ER-2 (N806NA)

ALTITUDE:65,000 FT

TRUE SPEED:410 KTAS

SWATH WIDTH:18.8 KM

Physics & Aerodynamics

1976 US STD ATM

True Airspeed (TAS)

410 kts

Indicated Airspeed (IAS)

105 kts

Ambient Pressure

56.5 hPa

Ambient Temperature

-56.5 °C

COFFIN CORNER SPEED BUFFER 11.2 kts

Vs: 95.8 kts IAS: 105.0 kts Mmo: 107.0 kts

At 65,000 ft, air density is <6% of sea level. Only an 11.2-knot window separates catastrophic stall from high-speed shock-buffet.

Ground Swath & Resolution

GROUND SWATH (WIDTH) 18.8 km

PIXEL RESOLUTION (GSD) 19.8 m

AIR DENSITY (ρ) 0.088 kg/m³

COLUMN MASS ABOVE 5.5 %

NASA ER-2 High-Altitude Airborne Science Operations

🚀 Atmospheric Layer Physics

The ER-2 routinely traverses the tropopause (approx. 36,000–40,000 ft in mid-latitudes), penetrating deep into the stable, dry stratosphere. In this layer, ambient pressure falls below 60 hPa (0.87 psi), leaving over 94% of Earth's atmospheric mass below the aircraft, creating pristine conditions for astronomical and hyperspectral remote sensing.

⚠️ The "Coffin Corner" Regime

As altitude increases, true airspeed (TAS) must remain high to generate sufficient dynamic pressure (q = ½ρV²) on the ER-2's 103-foot wingspan. Simultaneously, the speed of sound drops due to colder temperatures. The narrow corridor where stall speed (Vs) approaches critical Mach buffet (Mmo) is known as the Coffin Corner—requiring extreme pilot precision and U-2/ER-2 full pressure suits.

🛰️ Satellite Calibration & In-Situ Chemistry

Operating as a surrogate satellite platform from Armstrong Flight Research Center (AFRC Building 703 in Palmdale, CA), ER-2 flights validate sensors for NASA Earth observing satellites (PACE, Landsat, Sentinel, TEMPO) and directly collect chlorofluorocarbon (CFC) breakdown products, stratospheric ozone, and volcanic sulfate aerosols.