Small airplane – looking for best motor/propeller combo – some benchmarks

27,206 Replies

Compared to situation few years ago – now you do not need to use 50g+ motor and 15g+ ESC  to get 1kg thrust. Mini quadcopter racing mania made small motors/ESC much better, cheaper and better in terms of thrust/weight. They are high-kV (usually) but for small planes this isn’t bad – you still need speed and not only static thrust.

So, my requirements for motor/esc combo:

  • Still have enough thrust for unlimited vertical (so at least 800g of thrust)
  • Have enough pitch speed for penetrating headwind and flying around (so at least 100km/h at WoT)
  • Efficient setup at low throttle – need ~40km range endurance (total trip, not one-side).

Easy to find benchmarks on web for first two requirements, but for last one – probably next to impossible, so i re-built my thrust measurement rig – made it very well balanced and smooth as possible. Now it’s easy to measure even 1g of thrust (but probably would break away at full throttle):

stendas

Triple current measurement, triple voltage control, RPM measurement and precise PWM output.

Four motors, all completely new:

  1. EMAX RS2205 2300kV (Red Bottom)
  2. Racerstar BR2205 2600kV
  3. RCX 2206 2400kV
  4. Cobra 2204 2300kV (killed one Cobra together with FVT 20A BLHELI_S on plane – probably defective ball bearing on motor)

ESC – Racerstar 20A BLHELI_S, Medium timing.

Few props:

  1. HQ 5×3 (“Classic” propeller for noobs =)
  2. HQ 5×4
  3. DAL 5040 (thin version – IIRC there is another, “wide” version)
  4. DAL 5045 (thin)
  5. DAL 5045 BN
  6. DAL 6045 cut to 5545 (DAL 6045_C in graphs)
  7. GF 5550 (my current baseline – was using them on minicopter with gimbal)
  8. DAL 6045
  9. GF 6040
  10. GF 6045 (stupid centering rings)
  11. HQ 6045
  12. HQ 6030 (my old favorite – was working so well two years ago… Well, things changed =)
  13. DAL 6045 BN
  14. Graupner 6565 speed (this one from radjet remains – just to check for pitch speed)

props

So, what was done:

  • For each motor – measured voltage/current/thrust/RPM (bold columns in excel), everything else is calculated
  • For my Wing Wing Z (~500g AUW) ~120g of thrust is required to maintain level flight, so i only measured thrust at 1A and 2A (EMAX RS2205 got more measurements, but they aren’t required) – generated thrust is enough
  • Pitch speed is calculated based on propeller pitch data and RPM, not measured. All propeller unloading at higher speed, measurement inaccuracy and so on is not taken into account.

So, “best combo” should:

  1. Provide best g/W value at approx 120g of thrust
  2. still fit into tail of WWZ (7″ at max, for practical usage should be limited to 6.5″), 2-bladed (nobody wants to break multi-blade prop on every landing)
  3. Be as light as possible
  4. provide good enough pitch speed (you do not need much static thrust on plane)

So, results in short:

eff_2a

Cobra is doing very well in this test…. But we do not need 2A to cruise?

thr_1a

So, yes. It’s is possible to cruise using only 1A with all that weight and stuff if you have right motor.

But what about pitch speed? Currently using EMAX RS2205 on plane, so this motor in details:

thr_vs_maxspd

Not possible to get everything (eff + pitch speed) in one piece but still, some propellers clearly are better than others.

Full sheet:

Motor test sheets, excel format

Some may ask “hey, difference is way too small, why bother”? Yes, if you are just flying around in park – sure, you just put random motor/prop combo and go fly.

Others will tell – hey, some already did 70km+ on this wing, just copy this combo? Well, no. This setup was made as light as possible, without FPV equipment, with very weak motor (and battery, too), not much fun, actually.

Based on this data – you can easily make ~20% difference between “good” and “very good” motor+prop combo. This is actually a lot – i can have ~25km range now without any extreme power saving. +20% would make this 30km+ already.

So, best combos:

  • Cobra 2204 2300kV + GF 5550 – best overall combo. Lighter than other setups (4g saved == +60mAh on battery, do not forget about CG), good pitch speed and good enough efficiency
  • Cobra 2204 2300kV + DAL 6045 – most efficient combo. Very light and even more efficient than GF5550
  • EMAX RS2205 2300kV + GF5550 – fastest and still efficient combo , but not so efficient/light as Cobra (currently using this one on WWZ, 150km/h on level flight is not hard task for this motor).

27,206 thoughts on “Small airplane – looking for best motor/propeller combo – some benchmarks”

  4. Active167

    Discover affordable alternatives to the brand-name medication with amoxil , supplying broad-spectrum therapy for bacterial infections.

  8. Vivod iz zapoya v stacionare_slMa

    После бурной недели бывает так плохо. А дела не ждут. Вывод из запоя в стационаре — Круглосуточно. И только после этого становится легче. Капельница вывод из запоя — Без лишних вопросов. Вся информация доступна здесь: вывод из запоя стационар цены [url=https://pohmelye.vyvod-iz-zapoya-v-staczionare-volgograd.ru]вывод из запоя стационар цены[/url] И про детоксикацию в Волгограде. Обращайтесь к специалистам.

  11. Narkologicheskaya pomosh_jaPr

    Бывает, человек сам хочет завязать. Чтобы снять интоксикацию и подготовить организм. Кодирование наркологическая помощь — Осматривает, ставит капельницу. Сначала уходит интоксикация. Выездная наркологическая служба — И в выходные. Можете ознакомиться по ссылке: служба наркологической помощи [url=https://kodirovanie.narkologicheskaya-pomoshh-volgograd-jmn.ru]https://kodirovanie.narkologicheskaya-pomoshh-volgograd-jmn.ru[/url] И про срочный выезд для Волгоградской области. Не откладывайте на потом.

  13. Ancillarym451

    For those seeking relief from glaucoma, ozempic offers a swift and effective solution. Ensure to seek advice from a healthcare provider before starting treatment.

  15. Pharma133

    Protect your health by considering a treatment option widely discussed for certain conditions. Now, purchase lasvegas-nightclubs.com safely and efficiently, backed by scientific discussion and expert guidance to ensure your well-being.

  17. anapuNem

    Магазин DIESELHARDSHOP поставляет оригинальные автозапчасти для легковых и грузовых иномарок и спецтехники. Специалисты магазина диагностируют и ремонтируют топливную аппаратуру. Ищете онлайн интернет магазин автозапчастей? Каталог и заказ доступны на сайте dieselhard.shop для физических и юридических лиц. Отправка заказов по всей России идёт через СДЭК. Оформление заказа занимает пару минут.

  19. EMiller3

    For those seeking relief from gout or arthritis-related discomfort, consider exploring ozempic . Acquire this medicine online to potentially minimize your symptoms efficiently.

  22. MedSpot

    Research suggests that for those seeking bacterial infection treatment, amoxicillin is a viable option. Explore purchasing this antibiotic online for a convenient and effective solution to your health concerns.

  26. ozempi_find29

    For individuals seeking a cost-effective solution for their gastrointestinal health, ozempic dosage offers a viable option. Discover our wide selection of medications that provide relief and support for various conditions without compromising on quality or efficacy.

  33. Vivod iz zapoya v stacionare_pdKi

    Помню, соседка рассказывала. Никто не знал, что делать. Выведение из запоя в стационаре — И без доступа к алкоголю. Потом стабилизируют состояние. Вывод из запоя стационар — Без лишнего риска. Вся информация доступна здесь: вывод из запоя стационар в волгограде [url=https://kapelnica.vyvod-iz-zapoya-v-staczionare-volgograd.ru]https://kapelnica.vyvod-iz-zapoya-v-staczionare-volgograd.ru[/url] Там и про вывод из запоя стационар цены для Волгоградской области. Иногда стационар — единственный выход.

  34. Vivod iz zapoya v stacionare_fdKl

    Помню, сосед три дня не выходил из квартиры. Запой жуткий, сам не остановится. Детокс вывод из запоя — Круглосуточно. И только после этого начинают основное лечение. Капельница вывод из запоя — работает и в тяжёлых случаях. Советую глянуть источник: вывод из запоя в стационаре [url=https://detoks.vyvod-iz-zapoya-v-staczionare-volgograd.ru]вывод из запоя в стационаре[/url] И про детоксикацию по городу. Не ждите, пока станет хуже.

  37. Kodirovanie ot alkogolizma_gjOi

    Но сам не смог, срывался снова и снова. Жена уговорила его на кодирование. Кодирование от алкоголизма — И объясняют, как жить дальше. Само по себе кодирование не лечит. Кодирование от алкоголизма в Казани — И без постановки на учёт. Можете ознакомиться по ссылке: закодировать в казани [url=https://narkologiya.kodirovanie-ot-alkogolizma-kazan-fat.ru]закодировать в казани[/url] И про анонимное кодирование по городу. Иногда кодировка — это шанс начать заново.

Leave a Reply

Your email address will not be published. Required fields are marked *