Weight & Balance
Why is ballast always placed as far away as possible from the CG limit that is being corrected?
Answer
Because a longer arm means less ballast weight is needed to produce the same CG shift
The handbook's own example notes that if the ballast could have been placed farther forward, such as being bolted to the engine firewall, less ballast would have been needed—and adds that this is why ballast is always placed as far away from the affected limit as possible. The longer the arm between the ballast and the desired CG, the smaller the weight required to move the CG the same distance.
Source: FAA-H-8083-30B, Ch. 6 p. 6-23 — 'Use of Ballast / Permanent Ballast'
Not the answer
- Because the aircraft must be re-weighed if ballast is placed near the datum
- Because ballast located near the limit will be crushed by flight loads
- Because ballast must never be installed inside a baggage compartment
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