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Does anyone know how heavy are the combined landing gear on a Boeing 747?

It would be interesting if someone has also weight statistics per gear (nose gear and the four other main gear).

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    $\begingroup$ I don't have those figures, but if it helps, here are the moment changes for gear retraction, i.e. gear down to gear up and a negative moment is a forward change: Nose -167900 lb-in, Body -545600 lb-in, Wing -493900 lb-in. The figures are from Boeing Document No. D04U544-GPR1 for a 747-400BCF. $\endgroup$ – Terry May 30 '15 at 6:43
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    $\begingroup$ It could help the answerers to orient better if you can add the reason you need this info. What is the definition of the mass, that you are searching for (hydraulics included or not, brakes, doors, included or not, etc). Rule of thumb is that (for pre-sizing of aircraft) you can take 5-8 percent of the mtow. $\endgroup$ – Gürkan Çetin May 30 '15 at 8:37
  • $\begingroup$ @GürkanÇetin: Your percentage is a little high. 3% to 5% is normal, details depending on gear length and maximum sink rate. $\endgroup$ – Peter Kämpf Sep 12 '16 at 19:16
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It seems I misspoke in my comment in which I gave the moments for 747-400BCF gear retraction. I didn't realize the component weights were further on in the document I referenced. The weights for the BCF are:

body gear 6447 lbs (2924 kg) each

wing gear 6508 lbs (2952 kg) each

nose gear 3157 lbs (1432 kg)

However, @Gurkan's comment is relevant in that you have to decide what all should be considered as part of the gear. So, I put up a PDF of the WEIGHT AND BALANCE CONTROL AND LOADING MANUAL for each of two 747 freighter variants. You can access them at terryliittschwager.com/wbmanuals.php. The most relevant sections are 1-86-041 and 051.

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    $\begingroup$ I love that the nose gear of a 747 is considerably heavier than an entire fully loaded Cessna 172. $\endgroup$ – Peter May 30 '15 at 23:03

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