mrfox
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Space monkey
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The counter-argument to this is that having a clear delineation around the freezing point of water plays a much more important role in identifying hazardous weather conditions in our day to day lives. 32f is rather arbitrary given the major effects freezing water has on our eco-system.
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What is even more suspicious is how close 1 imperial foot is to 1 light nanosecond. It does make it really easy to guesstimate astronomical distances in conversation.
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A day cycle is important because day/night. Year because of seasons. 4 weeks roughly follows the lunar cycle and hence - tides. But why should the 12 month cycle be kept besides convention?
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Short Lifetime For Nuclear Thermal Rockets In Space?
mrfox replied to Spacescifi's topic in Science & Spaceflight
Could you elaborate on this? Is this a scenario where there is an established infrastructure of nuclear space tugs? or is the mass trade off for shielding so great that it is better to have a (baseball analogy) pitcher/catcher setup on either end even for a single use mission? -
A droplet of balm for the "green power" fans
mrfox replied to kerbiloid's topic in Science & Spaceflight
In a later post you referred to the “BSHP island” for reciprocating piston engines. In a gas turbine (or any turbine really) this island is absolutely minuscule in comparison - basically, anything other than near max rated power at close to max rated RPM - efficiency falls off a cliff. This is because while the compression ratio and efficiency is mechanically fixed (and independent of RPM) in Otto/diesel cycle engines, it is highly variable with RPM in a gas turbine/brayton cycle engine - the spinning compressor absolutely depends on being at high RPM to achieve anything near design compression. Just look at an idling gas turbine’s fuel consumption - it is horrendous in comparison to a piston engine. And turbines also take forever to spin up - so its not like you can just shut the turbine off Willy nilly like a piston engine to avoid idling either. -
Not saying it proves anything for what happened in the movie, but I do wonder how the spitfire compares with the shrike in terms of L/D ratio? A quick google shows the spit’s L/D max out around 13 at best glide... nothing found for the shrike.
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totm october 2020 Airplane Design Q&A
mrfox replied to mikegarrison's topic in Science & Spaceflight
The USAF has airstream trailers that can be bolted in for use as VIP transport. -
Here’s the FAA’s take on seizures and epilepsy. https://www.faa.gov/about/office_org/headquarters_offices/avs/offices/aam/ame/guide/app_process/exam_tech/item46/amd/nc/ I was not aware of such a thing as Rolandic epilepsy. I, like many others, had always assumed epilepsy is automatically disqualifying. Interesting. I would suggest a “off the record” consultation with someone familiar with aviation medicals in your country.
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plus pretty much all coffee grounds are full of roach parts. same reason no one bats an eyelid at hot dogs either.... its all about the packaging (and lots of seasoning).
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Interesting point - I am surprised at how much nitrogen the cycle can lose due to off-gassing. https://nutrientstewardship.org/implementation/nitrogen-loss-pathways-which-is-yours/ If rainfall, irrigation (>1/2 in. within a few days after application), or tillage do not soil incorporate surface-applied urea or urea-containing N fertilizers within a few days after application, ammonia volatilization (gaseous loss as ammonia) may range from 20 to 40% of the N applied, and rival N losses from leaching and drainage. Gaseous loss of N from soils as nitrous oxide (a potent greenhouse gas affecting climate change), through nitrification and denitrification processes, is often <2 to 8 lbs of N/A in humid regions and may be <1 to 2 lbs/A in less humid regions (e.g. west of the Mississippi River).