A launch site has a field elevation of 3,000 feet, and the current altimeter setting is 28.5" Hg. Using the altimeter setting conversion table on the Density Altitude Chart (Figure 8), what pressure altitude should the remote pilot use as a starting point to evaluate whether high density altitude will require reducing the small UA's takeoff weight?

Why: Figure 8's altimeter setting conversion table lists a conversion factor of +1,340 for an altimeter setting of 28.5" Hg. Pressure altitude is found by adding the field elevation and the conversion factor: 3,000 ft + 1,340 ft = 4,340 ft. The remote pilot then uses this pressure altitude, together with the outside air temperature, to read density altitude from the chart and judge whether the day's conditions require a weight reduction before flight.

• Subtracts the conversion factor instead of adding it; that sign would only be correct for altimeter settings above 29.92" Hg, not for a setting below it like 28.5" Hg.
• Skips the correction factor entirely and assumes pressure altitude always equals field elevation, which is only true when the altimeter setting reads exactly 29.92" Hg.