Metric/US measurement follies

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Rich
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Metric/US measurement follies

Post by Rich »

I was perusing the DA40 TDI POH the other day and noticed that with long-range (i.e. 40 gallon) tanks it has the same aft CG limit as the 50-gallon DA40-180. There are two different loading envelopes that depict this. But it has this statement referencing the long-range tanks:

Most rearward flight CG:
2.55 m (102.0 in) aft of Datum Plane


If course, the 2.55 m value agrees with the diagram but the conversion to US units is in error.

Years ago a simple error like this in a maintenance manual caused me to lose a valve in a motorcycle. And the incident known as the "Gimli Glider" flameout was also caused in part due to a conversion error like this.
2002 DA40-180: MT, PowerFlow, 530W/430W, KAP140, ext. baggage, 1090 ES out, 2646 MTOW, 40gal., Surefly, Flightstream 210, Orion 600 LED, XeVision, Aspen E5
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Diamond_Dan
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Re: Metric/US measurement follies

Post by Diamond_Dan »

Mars Climate Orbiter. Classic.
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