### Author Topic: N-1 rocket's grid fins  (Read 4003 times)

#### whitelancer64

##### N-1 rocket's grid fins
« on: 01/18/2019 05:43 pm »
My question is: what is the surface area of the N-1 rocket's grid fins?

I've been poking around a bit but I haven't been able to find the answer to this question. Best I've got so far is that they were 2.87 meters square, but no clue to how tall they were or how many "grids" are in them. Not sure about their dimensions, size, anything like that either.

Does anyone here know this info already?
"One bit of advice: it is important to view knowledge as sort of a semantic tree -- make sure you understand the fundamental principles, ie the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to." - Elon Musk
"There are lies, damned lies, and launch schedules." - Larry J

#### whitelancer64

##### Re: N-1 rocket's grid fins
« Reply #1 on: 01/18/2019 07:39 pm »
Holy crap! I found pictures on Twitter showing some N-1 grid fins had been used to build a picnic shelter. Wow.

Well, this allows me to at least get a count of how many cells there are on the N-1 grid fins. They are 20 cells high and wide. Grid fin is 2.87 m on a side, so each cell is about 15 cm wide.

I still don't know the depth, but if I assume ~30 cm for that (it looks to be about 2 cells deep), I can estimate the surface area.

287x30 = 8,610 cm2
30x15 = 450 cm2
9,060x2 = 18,120 cm2 per long rectangular cell.

18,120x20 = 362,400 cm2 or 36.24 m2

If it's more like 20 cm deep, then

287x20 = 5,740 cm2
20x15 = 300 cm2
6,040x2 = 12,080 cm2 per long rectangular cell.

12,080x20 = 241,600 cm2 or 24.16 m2

I'm not so good with the maths, but that sounds about right?
"One bit of advice: it is important to view knowledge as sort of a semantic tree -- make sure you understand the fundamental principles, ie the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to." - Elon Musk
"There are lies, damned lies, and launch schedules." - Larry J

#### whitelancer64

##### Re: N-1 rocket's grid fins
« Reply #2 on: 01/18/2019 08:11 pm »
Based on the below image, and a bit of area maths.

The Saturn V fin has a surface area of about 21,335 in2 or 137,646 cm2 or 13.76 m2 -- which means the N-1 grid fin has about twice the surface area as the Saturn V fin!
"One bit of advice: it is important to view knowledge as sort of a semantic tree -- make sure you understand the fundamental principles, ie the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to." - Elon Musk
"There are lies, damned lies, and launch schedules." - Larry J

#### Hobbes-22

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##### Re: N-1 rocket's grid fins
« Reply #3 on: 01/19/2019 08:32 am »
The book N-1 for the Moon and Mars has a dimensioned drawing.

LxWxD: 2800 x 2800 x 20 mm

#### whitelancer64

##### Re: N-1 rocket's grid fins
« Reply #4 on: 01/23/2019 02:36 pm »
The book N-1 for the Moon and Mars has a dimensioned drawing.

LxWxD: 2800 x 2800 x 20 mm

Thank you!!! That helps answer my question

280x20 = 5,600 cm2
20x15 = 300 cm2
5,900x2 = 11,800 cm2 per long rectangular cell.

11,800x20 = 236,000 cm2 or 23.6 m2
« Last Edit: 01/23/2019 02:38 pm by whitelancer64 »
"One bit of advice: it is important to view knowledge as sort of a semantic tree -- make sure you understand the fundamental principles, ie the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to." - Elon Musk
"There are lies, damned lies, and launch schedules." - Larry J