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Groundspeed limit applied to a miles-per-hour reading

Remote Pilot (Part 107) practice question 1 of 34 on Regulations / Operating Rules. ACS element UA.I.B.K21c · difficulty: applied. Want to answer it in a timed quiz? Use the Remote Pilot (Part 107) practice mode.

Question bank updated 2026-09-22

QUESTIONA remote pilot's control station displays the small unmanned aircraft's groundspeed as 95 miles per hour. Under § 107.51(a), is this speed within the operating limitation?

  1. ANo; the limit is 87 miles per hour
  2. BYes; the limit is 87 knots, which is 100 miles per hour
  3. CNo; the limit is 87 knots, which is about 80 miles per hour
Show the answer and explanation

Correct answer: B. Yes; the limit is 87 knots, which is 100 miles per hour

  • A — incorrect The figure 87 in § 107.51(a) is in knots, not miles per hour; the equivalent limit in miles per hour is 100.
  • B — correct § 107.51(a) states that groundspeed may not exceed 87 knots (100 miles per hour), so 95 miles per hour is within the limit.
  • C — incorrect § 107.51(a) itself gives the miles-per-hour equivalent of 87 knots as 100, not 80.

BACKGROUND

Section 107.51 of 14 CFR part 107 sets the operating limitations that the remote pilot in command and the person manipulating the flight controls must obey. Paragraph (a) limits the groundspeed of the small unmanned aircraft to 87 knots, and the regulation itself gives the equivalent as 100 miles per hour. Because a knot is a nautical mile per hour, the same speed reads as a larger number in miles per hour. A control station that shows miles per hour must be compared against 100, not 87. The other limitations in § 107.51 cover altitude, minimum flight visibility, and cloud clearance.

STUDY TIP

Memorize both numbers together, 87 knots and 100 miles per hour, and check which unit your display uses before comparing.

KEY POINTS

  • § 107.51(a): groundspeed may not exceed 87 knots (100 miles per hour).
  • A miles-per-hour reading is compared against 100, not 87.
  • The regulation itself supplies the miles-per-hour equivalent, so no conversion is needed on the test.

SOURCES

  • 14 CFR 107.51(a)
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MORE ON REGULATIONS / OPERATING RULES

SkyDrill is not affiliated with the FAA. This is an original practice item based on 14 CFR part 107, 14 CFR part 89, and the FAA Remote Pilot – Small UAS Study Guide (FAA-G-8082-22). Regulations and handbooks are revised; confirm details against the current edition.