May 23, 201115 yr Any of you fellas know why the first stage F-1s on the Saturn V was kerosene fuelled but the other J-2 stages were Hydrogen fuelled? Just wondering? ...keep it simple
May 24, 201115 yr Author Any of you fellas know why the first stage F-1s on the Saturn V was kerosene fuelled but the other J-2 stages were Hydrogen fuelled? Just wondering? ...keep it simple No. Go on then...
May 24, 201115 yr Any of you fellas know why the first stage F-1s on the Saturn V was kerosene fuelled but the other J-2 stages were Hydrogen fuelled? Just wondering? ...keep it simple So it keeps the heavy end down and the thing pointed up, twit! Hydrogen has a negative weight don't you know! This is not a Lawn Dart! Edited May 24, 201115 yr by copemech
May 24, 201115 yr Any of you fellas know why the first stage F-1s on the Saturn V was kerosene fuelled but the other J-2 stages were Hydrogen fuelled? Just wondering? ...keep it simple First stage is burnt in our atmosphere and the second stage is burnt in space. Which button do I push?
May 24, 201115 yr Author So it keeps the heavy end down and the thing pointed up, twit! Hydrogen has a negative weight don't you know! This is not a Lawn Dart! Doh! Should have guessed. Although the stability control system should be able to compensate for that.
May 24, 201115 yr Author Right?..so it's just a payload/weight issue....I see...I think ? ? No, lower centre of gravity (which a heavier fuel will give you) will result in more stability. Could also be that the parafin/kerosene gives more energy per kg burned than hydrogen. This is important when you need to overcome air resistance and gravity. It would also help that the heaviest part is dumped first. Edited May 24, 201115 yr by TooFastTim
May 24, 201115 yr No, lower centre of gravity (which a heavier fuel will give you) will result in more stability. Could also be that the parafin/kerosene gives more energy per kg burned than hydrogen. This is important when you need to overcome air resistance and gravity. It would also help that the heaviest part is dumped first. So it's a density/volume/ energy conundrum? Er..so we are we talking about 'high specific impulse' values of propellants? I was more inclined to think that suitable insulation of the cryogen from those 5 mighty F-1 torches was the main reason? as RP-1 (Kerosene) has a much higher boil-off point than liquid hydrogen. I always thought liquid methane was the boyo !... but what do I know?
May 25, 201115 yr I was searching for something about the weight and energy density of H2. This gives some idea. Myth 4
May 25, 201115 yr Note as attached to above, same principals apply to Kerosene, yet at some point one also gets into the the freezepoints and flowpoints of the fuels in a sub zero environment I would think. The more I think about this, it raises the question of weather H2 requires a warmup after a cold soak in a lunar orbit and prior to a return burst? I have not researched this at all. Just throwing it out as food for thought. What is the temp of space?
May 25, 201115 yr Author What is the temp of space? Where? Varies but around 20K in the shade. Then again you can't really talk about the temp of space. Temp is a measure of energy in matter. Space is (more-or-less) a vacuum. So it doesn't really have a temp. But radiation can cause temperature.
May 25, 201115 yr Author No, lower centre of gravity (which a heavier fuel will give you) will result in more stability. Could also be that the parafin/kerosene gives more energy per kg burned than hydrogen. This is important when you need to overcome air resistance and gravity. It would also help that the heaviest part is dumped first. Bearing Copeys post in mind I'll amend this to: Could also be that the parafin/kerosene gives more energy per gallon burned than hydrogen.
May 25, 201115 yr Note as attached to above, same principals apply to Kerosene, yet at some point one also gets into the the freezepoints and flowpoints of the fuels in a sub zero environment I would think. Never mind sub-zero space , remember what happens when there's a touch of moisture in this here kerosene stuff http://news.bbc.co.uk/1/hi/8504734.stm What is the temp of space? They were never that hot, even in their heyday ( is that you Cope at No. 69?) In direct sunlight: anything up to 120c and in the shade : anything down to -270c
May 26, 201115 yr They were never that hot, even in their heyday ( is that you Cope at No. 69?) In direct sunlight: anything up to 120c and in the shade : anything down to -270c JeeZe, where do you find this music?
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