mrfox

From my reading of the same book - Nolan, from his statue in hollywood, pretty much took over the creative writing once he came onboard the project. He decided crop blight to be the reason to abadon the planet not because it made sense, but because he had a thing for the depression era dust bowl imagery. The rest of the plotline as presented in the book seems to follow the same pattern of putting the (this will look good on the screen) cart in front of the (make the physics and story fit around the above) horse.

What really disappointed me about interstellar was that there was such potential for a much greater and meaningful story - the trailers for the movie (especially no.1 and 3) still gives me goosebumps, and manages to take my imagination further than the actual movie itself ever did.

Along the same lines, while white makes sense for EVA suits, orange or some other florescent color would have made a lot more sense for flight suits to aid search and rescue.

And 1 light nano-second is just about equal to 1 foot And 1 light nano-second is just about equal to 1 foot

Its about the cost vs benefit trade-off of risk mitigation - how much are you giving up by wearing the suits vs the potential risk mitigated with the suit. The challenger analogy in this case is rather apt - not in terms of o-rings and launch rules, but how the entire shuttle was designed without a LES in the first place - using reasoning similar to what you are trying to present here.

Thanks Mike. How much performance do you think is being given up with the fixed blades setup vs a variable pitch setup - mechanical complexity non-withstanding?

I've always wonder how turbofans - effectively a fixed pitch ducted fan - deals with this blade AOA/aircraft speed mismatch - I know the intake cowlings mitigates this somewhat by reducing intake velocity, and variable stator vanes alters the downstream pressure, but I was wondering if anyone can provide or knows of a detailed treatment with numbers they can share. Regarding sim fidelity - there is a reason NASA still sends canidates on T-38 rides. Operating a real machine teaches something called "mechanical sympathy" - and you learn quickly that "jamming inputs to the limits" is not good operating practice for a real life machine, nor the real life operator. "Slow is Smooth - and Smooth is Fast"

Surface coking of components would be an issue. Potential "worlds worst/most dangerous job" episode idea - who wants to be first to sign up to do a space walk...to go inside a rocket engine... to scrub off skid marks...

Kruger flaps generally have inferior performance aerodynamically, but they are vastly simpler structurally and hence lighter - especially when considered in conjunction with anti-ice systems that uses hot bleed air in the leading edge (most large civil aircraft excluding the 787). With slats, you need to run hot telescoping metal pipes through a ice cold air gap to deice them. Which makes for a heavy and somewhat unreliable system, with very dangerous failure modes (hot bleed leak near fuel, hydraulics, wing structure...)

What sort of coolant pressures would this hydrogen based refridgeration system be working at to reject heat at 800-1200K?

What would be the realistic minimum crew complement for a long duration, self sufficient deep space mission? I envision a 6 crew ship - 3 rotating shifts of an engineer and a doctor on duty - providing backup to cover for contingencies where some crew are knocked out of commision. Also spare crew to provide support for EVA, complex repairs or surguries. Could everything else be entrusted to automation or remote command?

http://www.projectrho.com/public_html/rocket/crew.php

Boeing has a bit of a history of sinning first and asking for forgivness later. Sadly, the FAA also has a bit of a track record of caving to Boeing demands - as in this following example regarding a change to the lightning protection on the 787 that happened last year. https://www.seattletimes.com/business/boeing-aerospace/faa-engineers-objected-to-boeings-removal-of-some-787-lightning-protection-measures/ The FAA initially rejected the removal of the foil from the wing on February 22, when its certification office ruled that Boeing had not shown, as regulations required, that the ignition of fuel tank vapor by a lightning strike would be extremely improbable, defined in this case as likely to occur no more than three times in a billion flight hours. By then Boeing had already built about 40 sets of wings without the foil. Facing the prospect of not being able to deliver those airplanes, Boeing immediately appealed. FAA managers reversed the ruling exactly a week later — just days before the unrelated crash of the second 737 MAX.

GBAS equipment is actually lower cost compared to current ILS arrays - both in terms of initial investment, and on-going mainteniance. ILS tech is based on old school analog signals that requires large, power hungry antennas and frequent recalibration. GBAS and GLS tech are firmly in the digital age with their associated advantages of signal consistancy and power efficiency. Whether an autopilot can be "smoother" is debatable - they work through the same control surfaces as a human pilot - and fly-by-wire can actuate certain combinations of control movements to achieve things that are not available to a operator using traditional controls - gust alliveation being a example of this - where alierons on both sides are driven up to unload the wings to reduce gust loading. I can tell you through personal experience that the autoland functions in the current gen airliners can land as smoothly as any human given the right conditions. My current airplane's crosswind limit for autoland is the same as its crosswind limit under manual flight. What automation excels at, however, is consistancy. Where you state "a computer will always land, more or less, the same way" - this is the very advantage of an automated system. The reason they can feel "rough" is because the software is designed to land the airplane in a defined touchdown zone. A human pilot might decide on the day to let the airplane float a bit to achieve a smooth touchdown, whereas the autoland will drive it down to keep it within tolerances. The problem arises when human pilots do this and land long, they miss a high speed turn-off or two, resulting in longer runway occupancy times, increasing seperation, and causing the occasional go-around for aircraft following behind. A fully automated system using GBAS/GLS can actually reduce seperation requirements even beyond current limits. An example of this performance consistency can been seen when the MQ9 UAV (which unlike the RQ4, have conventional remote controls fitted) went full autoland - the runway requirements went down by 1000 ft due to the consistancy the autoland was able to achieve. As much as I personally enjoy landings and manual handling - at the end of the day - the autopilot is a more consistant performer.

With next gen GPS and GBAS (Ground based augmentation systems) - the above mentioned limitations of the older current gen ILS (instrument landing system) really no longer applies. GBAS can land aircraft with a margin of error measured in centimeters and does not have the spacing or signal interference issues of an ILS, as it no longer requires line of sight between the ground transmitter and the aircraft reciever. The global hawk RQ4 UAV uses a mobile, self contained version of GBAS, and landings are fully automatic - in fact there are no provision for controls at all for manual intervention. Just as the manual skills of holding a precise altitude for cruise, tuning a radio by ear, or adjusting mixture and spark by feel has much been taken over by automatics, so will go the skill of landing a airplane using stick, throttle and rudder - eventually. However, takeoffs and landings are just a small part of what being a pilot entails. - From the stories of various mishaps and failures I've heard so far from RQ4 operators due to their lack of an onboard operator for real time decision making and logic check - a manned presence for ultimate decision making onboard flights with live human cargo will be prudent for years to come. Because computers can still be incredibly stupid if you let it.

mental experiment does this following wing work under your assumption? Why or why not?

“On no other 737 is there a system based on the angle of attack that will move the (horizontal tail) trim. That is unique to the MAX,” said Cox, the CEO of the aviation consultancy. “I was surprised that a single angle of attack indicator could cause the activation of this system.” https://www.seattletimes.com/business/boeing-aerospace/faa-follows-boeings-737-safety-alert-with-an-emergency-directive/ note the description of the "auto-trim" feature for the 737 is completely wrong in this article. The STS is the exact opposite of auto-trim - more like an anti auto trim.

From what I can gather from various reports, it appears that unlike previous 737 generations, the STS in the MAX also takes data directly from the AOA probes.

Aircraft certification requirements include specific stick force requirements at various speed and power configurations in order to provide stable handling characteristics. When Boeing stretched the 737 these handling characteristics degraded, so they came up with the STS, which artifically increased these stick forces on the cheap by running the trim system the opposite way the pilot is pulling. It ticks the box for the FAA requirements but is utterly counter-productive for the pilot, as he/she will have just have to untrim these inputs later. It is a great example of how a bureaucracy can end up with the tail wagging the dog sometimes - a certification rule intended to provide ease of handling for the pilot ends up making handling worse by introducing counter-productive inputs in order to satisfy a "rule".

The system in question (and the subject of the EAD) is not the stick pusher, but the 737s speed trim system (STS). It is a stability "augmentation" system that adds trim in the opposite sense as airspeed and thrust settings change, in order to artifically increase the stick force required during manual flight. It is a very counter-intuitive system that trims against pilot input to create this additional stick force. All because the 737 is not naturally speed stable enough to meet certification requirements otherwise.

https://en.m.wikipedia.org/wiki/Clock_of_the_Long_Now Its a clock designed to run for "only" 10,000 years. But it shows the thought process of actually thinking through, accounting for, and designing around the issues of a device designed to work beyond the span of our civilization.

Mathamatically its a momentum exchange tether in reverse. Similar to what is described here - https://www.google.com/url?q=http://scholar.google.com/scholar_url%3Furl%3Dhttps://arc.aiaa.org/doi/pdf/10.2514/1.44873%26hl%3Den%26sa%3DX%26scisig%3DAAGBfm2VpLOITVrFPGnL9pQmXMIEjv9YTQ%26nossl%3D1%26oi%3Dscholarr&sa=U&ved=0ahUKEwi2656I19rbAhVl6oMKHWy8BosQgAMICygA&usg=AOvVaw3KSueYLqXEqnt0gjQjnV6O The structural requirements to intercept inbound objects at interplantery speeds would be substantial. Hopefully by that point in our evolution we have figured out better power sources - analogous to how modern solar panels have taken the place of mercury boilers in early sci-fi.

the question is less a physics problem, rather its a great lesson in how vaguely/poorly defined scenerios can cause angst and confusion - because everyone assumes their own 'obvious' assumptions to the question are... obvious.

These would be belts used for power transmission/timing/sync applications - similar to the belts you find in a car engine. Fastest conveyer belt is apparently 'only' 15m/s (30 knots) at a german mine

Quick google search shows max rated belt speeds today to be around 100m/s - around 200 knots - so it seems for high speed airplanes (most large airliners today have rated max tire speeds around 230 knots) both the belt and the wheels would fail around the same time. The belt would heat up just as much as the tires would due to the mechanical deformation of the material as it bends around the rollers.