LVP Approach DH's
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LVP Approach DH's
My company [744,777,340,330 operator] insists that all CATIIIa approaches throughout the world have a DH50ft [Fail Op or Fail Pass].
Jeppesen have CATIIIa approaches with DH0ft [RKSI 33R for example].
US FAR AC 120 -28 talks about CATIIIa with DH0ft [I haven't looked up JAR's].
Is this a case of 'Company Policy'?
Could anyone out there enlighten me please?
Jeppesen have CATIIIa approaches with DH0ft [RKSI 33R for example].
US FAR AC 120 -28 talks about CATIIIa with DH0ft [I haven't looked up JAR's].
Is this a case of 'Company Policy'?
Could anyone out there enlighten me please?
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F.L. CAT III A fail passive is DH 50 FT. CAT III A fail operational NO DH or 50 ft DH, can be both. Explanation: CAT III A with failed passive requires a DH of 50 for the PIC to be able to take over manually and complete the landing manually if deemed safe. CAT III A NO DH requires fail operational auto pilot system to complete the landing automatically. However in both cases RVR required is suitable for manual rollout or in other words auto roll out function isn't required for CAT III A approach. Jeppesen doesn't state CAT III minima unless you have customized charts. Usually the AWO mins require separate approval from relevant authorities and are depicted on company's separate sheet. 
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EU OPS is different in this regard, indeed CAT III A always implies DH thus it's 50 ft.
A category III operation is a precision instrument approach and landing using ILS or MLS. Category III is subdivided in category III A and in category III B.
Category IIIA approach is a precision instrument approach and landing with: - a Decision Height lower than 100 ft (30 m) and
- a Runway Visual Range not less than 700 ft (200 m) Category IIIB approach is a precision instrument approach and landing with:
- a Decision Height lower than 50 ft (15 m) or no Decision Height ; and - a Runway Visual Range less than 700 ft (200 m) but not less than 250 ft (75 m)
Note: Where the decision height (DH) and runway visual range (RVR) do not fall within the same Category, the RVR will determine in which Category the operation is to be considered.
A category III operation is a precision instrument approach and landing using ILS or MLS. Category III is subdivided in category III A and in category III B.
Category IIIA approach is a precision instrument approach and landing with: - a Decision Height lower than 100 ft (30 m) and
- a Runway Visual Range not less than 700 ft (200 m) Category IIIB approach is a precision instrument approach and landing with:
- a Decision Height lower than 50 ft (15 m) or no Decision Height ; and - a Runway Visual Range less than 700 ft (200 m) but not less than 250 ft (75 m)
Note: Where the decision height (DH) and runway visual range (RVR) do not fall within the same Category, the RVR will determine in which Category the operation is to be considered.
