How to calculate Index from %MAC Values
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Joined: Apr 2026
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From: Sweden
How to calculate Index from %MAC Values
How would I go about to calculate index from only %MAC values?
For example a Bombardier Global 7500 only operates in %MAC.
How would I translate that into Index values?
LEMAC: 670.560
MACLEN: 179.040
Is there a calculation for this?
For example a Bombardier Global 7500 only operates in %MAC.
How would I translate that into Index values?
LEMAC: 670.560
MACLEN: 179.040
Is there a calculation for this?
Joined: Jul 2006
Posts: 3
Likes: 0
From: oxford
Hi.
Index and MAC percent are two different things. MAC percent is a physical place. You can touch it.
Index is a convenient, dimensionless moment (usually scaled and offset so always positive)
Index = (((H_arm - ReferenceStation)* Mass of item) / ScalingConstant) +offset.
Substitute H_arm as percent MAC and rearrange formula.
H_arm= LEMAC+MAC*PercentMAC
Hope this helps.
Index and MAC percent are two different things. MAC percent is a physical place. You can touch it.
Index is a convenient, dimensionless moment (usually scaled and offset so always positive)
Index = (((H_arm - ReferenceStation)* Mass of item) / ScalingConstant) +offset.
Substitute H_arm as percent MAC and rearrange formula.
H_arm= LEMAC+MAC*PercentMAC
Hope this helps.
