What would be the best material to machine a replacement from for a sand-cast 356-T6 attachment fitting for a flight control surface? It is on a Constellation. Elevator attach, control side.
A cast flight control fitting? Sounds suspect. Are you sure it isn’t forged after casting?
MMPDS-01 Table 18.104.22.168(b) provides allowables. Suggest 6061-T651 per AMS-QQ-A-250/11 or AMS-QQ-A-200/8 due to superior strength, near identical stiffness, excellent machining, corrosion, fatigue, cost, etc…
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