Rate Of Climb Required
Calculator
Results
- Rate of climb required (ft/min)
- 972.222222
- Time (minutes)
- 5.142857
- Climb gradient (ft per NM)
- 416.666666
Aviation and marine results
| Rate of climb required (ft/min) | 972.222222 |
| Time (minutes) | 5.142857 |
| Climb gradient (ft per NM) | 416.666666 |
formula-map diagram
- Rate of climb required (ft/min)
- 972.222222
- Time (minutes)
- 5.142857
- Climb gradient (ft per NM)
- 416.666666
Aviation and marine relationship
Formula
ROC = altitude gain ÷ (distance ÷ GS × 60)= 972.22222222222
Note
This is a simplified model: it applies a standard navigation, performance or seamanship formula to the numbers you entered. True airspeed and density altitude use the ISA troposphere model for dry air and ignore humidity, compressibility and instrument or position error, so they are not a substitute for your aircraft's flight manual or an air data computer. Wind, climb, descent and fuel figures assume a steady wind and a constant speed and fuel flow for the whole leg; they ignore manoeuvring, holding, taxi and start-up fuel, terrain, turbulence and air traffic control routing. Takeoff distance scales an entered sea level figure by a rule-of-thumb percentage per 1000 ft of density altitude and is not a certified performance chart. Weight and balance results depend entirely on the arms and weights you enter and must be checked against the approved loading envelope. Hull speed is the classic 1.34 × √LWL displacement estimate, boat fuel burn is a horsepower-based approximation, anchor scope is a rule of thumb, and the rule of twelfths is a linear approximation of a sinusoidal tide that does not hold in all locations. Always use official charts, tide tables, the aircraft or vessel manuals and current weather, and treat these numbers as planning estimates only.
More in Aviation and marine
See all →Frequently asked questions
What does 'rate of climb required' mean in this context?+
It's the vertical speed, usually in feet per minute, that an aircraft must sustain to reach a target altitude within a given horizontal distance or time — for example, to clear an obstacle or meet a published climb gradient on a departure procedure.
How is required rate of climb calculated from a climb gradient?+
It's derived from groundspeed and the required climb gradient (often expressed as feet per nautical mile): required rate of climb = climb gradient × groundspeed ÷ 60, converting nautical miles per hour into feet per minute.
Why does groundspeed matter more than airspeed for this calculation?+
A climb gradient is a distance-based requirement (altitude gained per distance traveled over the ground), so it depends on how fast you're covering ground, not how fast you're moving through the air. A strong headwind reduces groundspeed and therefore reduces the vertical rate of climb needed to meet the same gradient.
What's a common mistake pilots make with climb gradient requirements?+
Confusing a percentage climb gradient with a rate of climb in feet per minute — they are not interchangeable without factoring in groundspeed. A 200 ft/NM gradient requires a very different vertical speed at 90 knots groundspeed than at 150 knots.
How does this relate to obstacle clearance on departure?+
Departure procedures often specify a minimum climb gradient to ensure obstacle clearance. If your aircraft's actual climb performance, converted to a gradient at your expected groundspeed, is less than required, you risk not clearing terrain or obstacles even though your indicated rate of climb looks adequate.