No more hassle with extra cables if you need to have both airspeed and external compass installed on your airplane. This board solves your cabling problems. Board has HMC5983 with LDOs and level-converters along with differential pressure sensor.
The Pixhawk digital differential airspeed sensor has a very low offset, a high resolution and, best of all, does not suffer from the noise induced by long cables and offsets in the ratio-metric output on the APM 2.6 analog airspeed sensor.
Featuring a Measurement Specialties 4525DO sensor, with 1 psi measurement range (roughly up to 100 m/s or 360 km/h or 223 mp/h), the Pixhawk Airspeed Sensor Kit enables a resolution of 0.84 Pa, with data delivered at 14 bits from a 24 bit delta-sigma ADC. It also measures temperature to allow calculation of true airspeed from indicated airspeed using the MS5611 static pressure sensor on Pixhawk. Not influenced by the heat of nearby processing components, it is much closer to the true air temperature than the previous analog sensor setups. Supported on all Pixhawk and PX4 autopilot generation boards, this kit has M3 (3/32in) mounting holes. Kit dimensions 34x20x10mm, distance between holes 29x15mm.
High accuracy HMC5983 compass with I2C level converters, filtering and LDOs are installed on board to make it a convenient packet for all airplane users. Pixhawk detects automatically the external compass and starts using it. External compass is always more accurate than internal due to magnetic interference inherent in internal compasses.