Does this powertrain add up?
A motor from the wrong weight class, a propeller nothing of this size carries, an ESC that cannot pass the motor's rated current β all of it shows up by comparing numbers, before any calculation. This page does exactly that comparison against published manufacturer specs, and then estimates how much the combination pulls β as a range, because what you leave blank is a range too.
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What an error here costs
A motor from the wrong weight class, a propeller nothing of this size carries, an ESC that cannot pass the motor's rated current β every one of those shows up by comparing numbers, before any calculation.
- An overloaded motor burns its windings in a single flight β and the load comes from the propeller, which is the cheapest part of the set.
- An ESC below the motor's rated current overheats and cuts power in the climb: the motor stops in the air, not on the bench.
- A propeller out of class loads the mount and the wing exactly when the model is lowest and slowest.
This page marks what does not add up. It never certifies a combination as safe β see βHow to check this yourselfβ below for why that is not the same thing.
What you need at hand β and where to take it from
- The motor itself β the size is printed on the bell or in the shop listing (β2806.5β, β4260β); the KV is next to it.
- The ESC label β the current rating in amps, and the pack label for cells, capacity and C rating.
- The airframe spec or a tape measure β the wingspan in millimetres and the number of motors.
Nothing here is mandatory and nothing should be invented: a number you do not know is not an input. Leave the field empty and the range typical for the class is used instead β visibly, with its source.
What do you know about the combination?
Fill in only what you know. Anything left blank is replaced by the range typical for the class β the answer stays honest and simply says what to clarify.
How much does it pull?
Checks
Who flies this combination
Published aircraft with the same motor and propeller: what else is on them and how they are built.
Show aircraft with this combinationAssumptions the verdict stands on
Nothing here is a fact about your aircraft β these are ranges typical for the class, substituted because the field was left blank. Clarify any of them and the answer narrows down.
Why nothing here picks the propeller for you
This page checks what you already have; it does not choose it for you, and that part is switched off on purpose. Choosing means ranking propellers, and the ranking would be built on how each one behaves in cruise. Cruise figures used to be understated by more than half; they are not any more β the model now follows the propeller's own thrust and power curves, and cruise thrust is off by about 6% on average. But the worst point is still 23% out, and an order of candidates is read as βthese ones fitβ, not as βthe error underneath is this bigβ. Whether that is good enough to open is a decision, not a calculation.
These percentages are shares of that propeller's static thrust (or power), not of the figure at that point: on a propeller pulling 1 kg on the bench, 10% means 100 g. They are counted this way because near the airspeed at which thrust dies the measured value itself goes to zero, and a share βof the local valueβ there says nothing about how far off the answer is β the same discrepancy would print as thousands of percent. Numbers published before August 2026 were shares of the local value and are not comparable with these.
They also describe a propeller whose size was wind-tunnel tested. Half of the catalogue carries the manufacturer's figures instead, and any in-between size you dial in is interpolated between neighbours β for those the error was measured separately, by taking the propeller's own entry out of the catalogue and rebuilding its coefficients from what is left: 16% on static thrust and 36.5% on current, on average. The row itself says which kind it is.
How big that error is, measured against wind tunnel data. The typical miss on static thrust is 5% on average and up to 20% in the worst point. The systematic offset is a different figure, and here it is small: 0.5%, too little for the measurement to say which side the model errs to. A small offset and a number you can trust are not the same statement, and the page keeps them apart for you. What it does not do is turn either of them into a shortlist of parts to buy.
Save this powertrain to your aircraft
The check is free and needs no account. An account is needed for the next step: keep the picked propeller, motor and ESC on your aircraft card, together with its batteries, flights and expenses.
Sign in or sign upMethod: comparison against published specifications, plus a thrust range
Every range on this page comes from a published manufacturer specification β the exact source of each one is listed next to the assumption it produced. Ranges are envelopes over real products of the class, not round numbers picked by hand: a class with no honest source answers βno reference dataβ instead of guessing.
How a verdict follows from those ranges:
- Does not add up β a published limit (the motor's rated voltage, the ESC rating, the pack's discharge) is broken for every value inside the ranges.
- Out of class β no aircraft in the reference is built that way. That is not the same as proven danger, and the page does not pretend otherwise.
- Adds up β holds for every value inside the ranges. Anything in between the two is left undetermined, with a list of what to clarify.
The thrust range is calculated, and differently: every unknown is drawn from its class range a few thousand times, and what comes back is the middle of those runs and the band most of them fall into β βabout 650 g, probably 480β820β. Whatever you fill in stops being drawn, so the band narrows; the page names the one unknown that narrows it most, instead of asking you to fill in forty fields.
That band covers only what you did not tell us. The error of the propeller model itself is a separate figure, measured against wind tunnel data and printed under the estimate β it is deliberately not baked into the band, because a band widened to swallow it would pass a known bias off as your uncertainty.
Sources:
How to check this yourself β and what is not checkable
Every number this page compares is printed on the parts you already hold: the motor's rated current and voltage on its listing, the ESC rating on its label, the pack's C rating on the pack. Open the source next to an assumption and you are reading the same page we did β that is the whole check, and it needs no bench.
What is not checkable here: propeller load. It follows from blade element theory, and that calculation is not validated against wind tunnel data yet β so this page shows a coarse warning there and no number at all. A pretty number without stated limits is worse than none, because people believe it literally.
The thrust range is checkable β with a scale and a running motor. That is the one dangerous step this page can send you to, so the procedure and its safety rules are not repeated here: they live next door, in the powertrain picker's manual. Expect the measured thrust to land below the estimate β the model runs high on static thrust, by the amount printed under it.
For the same reason the summary never says βsafeβ: four checks passing is not a statement about the fifth, and a thrust range is not a verdict at all.