For cresting a grade at a CG location, which statement best reflects SSI guidance?

For cresting a grade at a CG location, which statement best reflects SSI guidance?

• A. Crest at the maximum authorized speed.
• B. Crest at least 5 mph under the maximum authorized speed.
• C. Crest at 10 mph under the maximum authorized speed.
• D. Crest at least 5 mph under the maximum authorized speed.

Answer: (D)

When cresting a grade with the CG positioned as described, you want to stay inside the safe flight envelope while still achieving the required climb performance. The maximum authorized speed defines the upper limit for structural and handling safety. By cresting at least 5 mph below that limit, you maintain a comfortable margin for unexpected gusts, engine response, and any slight changes in pitch or configuration as you pass the crest and begin the climb. This cushion also helps preserve elevator authority and stall margins given the CG location, reducing the risk of overspeed or loss of control during the transition from crest to climb. Cresting right at the maximum would remove that safety buffer, increasing risk in real-world conditions. Being significantly more conservative (like 10 mph under) is more protective than necessary for this scenario, though sometimes used in other contexts; the guidance in this case emphasizes maintaining at least a small but consistent margin, specifically around 5 mph under the maximum.

When cresting a grade with the CG positioned as described, you want to stay inside the safe flight envelope while still achieving the required climb performance. The maximum authorized speed defines the upper limit for structural and handling safety. By cresting at least 5 mph below that limit, you maintain a comfortable margin for unexpected gusts, engine response, and any slight changes in pitch or configuration as you pass the crest and begin the climb. This cushion also helps preserve elevator authority and stall margins given the CG location, reducing the risk of overspeed or loss of control during the transition from crest to climb.

Cresting right at the maximum would remove that safety buffer, increasing risk in real-world conditions. Being significantly more conservative (like 10 mph under) is more protective than necessary for this scenario, though sometimes used in other contexts; the guidance in this case emphasizes maintaining at least a small but consistent margin, specifically around 5 mph under the maximum.