Winter 57mm ASI

(Inc. 20% VAT)
(£424.17 Exc. VAT)

Winter Instruments 6 FMS Airspeed Indicator 80mm 

Airspeed-indicators measure the difference between total pressure and static pressure. The total (or measured) pressure is sensed by a pitot tube positioned at the stagnation point of the airstream and is carried to the airspeed indicator by a hose. A static pressure sensor can also be connected. The measuring element is an open diaphragm unit with excellent elastic properties; hysteresis (differences between advance and return movement) and secondary elastic effects are negligible. The effect total pressure and static pressure acts on the diaphragm, causing a deformation, that is transferred to the pointer by a linkage and gear mechanism. The different operating ranges of the aircraft can be identified by colour markings on the airspeed indicator dial. The instruments are insensitive to shock and vibration.


Technical Data

Purpose: Pitot airspeed indicator for indication of the relative airspeed of gliders and micro–lights.

Principal mode of operation: The instrument works by measurement of the pitot pressure, by means of an open diaphragm cell, as difference between total pressure and static pressure.

Scale graduation:

  • 6 FMS 2 and 6 FMS 5: 360° scale with linear graduation
  • 6 FMS 4: 510° scale with non–linear graduation

Weight: 6 FMS 2, 6 FMS 4 and 6 FMS 5: 0,2 kg

Indication errors:

  1. at room temperature: 0–100 km/h:± 2 km/h above 100 km/h: ± 3 km/h
  2. at –30°C to + 50°C: 0–100 km/h:± 3 km/h above 100 km/h: ± 5 km/h

Factory Colour Marking

Colour markings can be put on the instrument scale to identify the operating ranges and the limiting performance of the aircraft. The type series numbers given in the above table are only applicable to types 6 FMS 2, 6 FMS 4 and 6 FMS 5 airspeed indicators without colour marking on the indicator scale. In all other cases, the part number should be obtained from the technical documents of the aircraft manufacturer or by checking with Gebr. Winter & Co. KG.

Please allow approximately 4 weeks Winter Instruments production time for Factory Installed Colour Markings.


Maintenance Instructions

Leak testing should be carried out at least every 2 years. Otherwise, the instrument does not require any maintenance.

The manufacturer recommends airspeed indicators be subject to retesting after 5 years.

Retesting and Repair

The service condition and accuracy of measurement of the ASI is normally retained over a long period. For obvious malfunction the unit should be subjected to an investigation at the manufacturer or a suitable aircraft engineering company. It should be packed to protect it from impacts and connections should be sealed. Under no circumstances should you interfere with the measuring mechanism of the airspeed indicator.

Application Limits

Maximum operating height: 12.000 m

Operating temperature range: –30°C to + 50°C

Magnetic Effect: No deflection of the compass needle at any distance between airspeed indicator and aircraft compass.

Overpressure resistance: The maximum indicated airspeed may be exceeded by 20%.

Vibration resistance: 5 – 50 Hz: maximum amplitude 0,25 m

maximum acceleration 1,5 g

50 – 400 Hz: maximum acceleration 0,5 g

Accompanying Documents

  • New Instrument
    Test certificate EASA Form One, POE
    Installation and maintenance instructions