The Lagos accident seemed to involve the loss of attitude control, so the same assembly would be the first cause of failure to examine.
Tuesday, June 5, 2012
Nigerian air crash
A plane identified as an MD-83 crashed in Lagos, Nigeria while attempting to land.
The MD-80 versions were modifications on the old DC-9. The vertical stabilizer was mounted at the top of the vertical stabilizer. The entire horizontal stabilizer was designed to rotate relative to the airflow. To accomplish this, there is a jack screw and powered nut assembly. The jack screw was attached to the stabilizer and forced its movement. The nut assembly was powered and caused the motion. There was an accident off the coast of California where the nut stripped and the screw assembly came loose causing the stabilizer to flap freely and causing the aircraft to crash causing the loss of all lives on board.
The Lagos accident seemed to involve the loss of attitude control, so the same assembly would be the first cause of failure to examine.
The Lagos accident seemed to involve the loss of attitude control, so the same assembly would be the first cause of failure to examine.
Saturday, May 5, 2012
Fast recon
F-35 shown obsolete on previous posts
t should be possible to build an unmanned follow on to the SR-71. The drone would be carried aloft by a carrier aircraft and released from a boom, see F-35 posts. It could be built with ramjet engines.
Ramjet engines are as efficient in thrust for airflow as turbine engines at about Mach 3.
At a little under Mach 4 they are as efficient as turbines by fuel flow. The airflow is the air swept into the engine inlet by forward movement. It allows fro the minimum inlet size and the minimum drag for a given thrust. Fuel flow is the rate a t which fuel is burned.
The drone could be used in the event of satellites being destroyed. It would be flown to a speed of over 600 mph and released . Its engines would initially be horribly inefficient but there relative efficiency would rise with increasing speed.
At the end of its surveillance run it would be captured by another manned aircraft and flown to the ground for reuse. Its advantage is high speed, high altitude flight in a package of minimum radr return. It could probably be built without vertical stabilizers, tails, as the high speed flight should allow for good rates of control.
Thursday, May 3, 2012
Laser bullets
F-35 shown obsolete on previous posts
In order to achieve greater accuracy attempts have been made to secure laser pointers on police handguns. The difficulty is that they become dislodged and consequently produce inaccurate fire. Another solution is to place the laser physically in the bullet.
The bullet would have to be a hollow point. The copper jacket of the bullet would be 1 electrode. An insulator, perhaps Teflon tape, would be wrapped around the bullet for electrical separation. The 2nd electrode would be the propellant case. an electric conductor would be swaged between the Teflon tape around the bullet and the case. A plastic tube would be installed into the case to allow propellant to be filled while leaving a space to insert the laser light tube.
The electronic package for the bullet would be installed on the pistol frame. The battery could be installed at eh bottom of the bullet clip, displacing 2 or 3 bullets.
Grips would be squeezed on the front and back of the pistol handle to connect the circuit and activate the laser. If the circuit fails, the pistol would still be operable.
A serious difficulty is placing the electrodes in the pistol chamber. The negative electrode would provide electrons which is what oxygen wants for reactions, there would be a severe danger of corrosion unless the electrode is isolated from the steel . A ceramic insert could be used to achieve this. There is a danger of dislodgement and jamming.
At a muzzle velocity of 350 meters per second, the bullet would drop about 0.1 meter, 10 centimeters at 50 meters range. The light tube might also be slightly misaligned and the laser light would spread over some area. But it should still have effective accuracy at 50 meters, if the laser has adequate light to be seen, particularly under sunlight.
This would be a war crime for military usage since the bullet is open ended. The idea would be to have it available only for police agencies to insure that police have an advantage in gunfights. In the U.S., the lunatic lobby would insist on everyone haveing access to them, which would really be a bad idea since it would make killings much easier.
The pistol would be more expensive and the bullets many times more expensive than conventional designs.
In order to achieve greater accuracy attempts have been made to secure laser pointers on police handguns. The difficulty is that they become dislodged and consequently produce inaccurate fire. Another solution is to place the laser physically in the bullet.
The bullet would have to be a hollow point. The copper jacket of the bullet would be 1 electrode. An insulator, perhaps Teflon tape, would be wrapped around the bullet for electrical separation. The 2nd electrode would be the propellant case. an electric conductor would be swaged between the Teflon tape around the bullet and the case. A plastic tube would be installed into the case to allow propellant to be filled while leaving a space to insert the laser light tube.
The electronic package for the bullet would be installed on the pistol frame. The battery could be installed at eh bottom of the bullet clip, displacing 2 or 3 bullets.
Grips would be squeezed on the front and back of the pistol handle to connect the circuit and activate the laser. If the circuit fails, the pistol would still be operable.
A serious difficulty is placing the electrodes in the pistol chamber. The negative electrode would provide electrons which is what oxygen wants for reactions, there would be a severe danger of corrosion unless the electrode is isolated from the steel . A ceramic insert could be used to achieve this. There is a danger of dislodgement and jamming.
At a muzzle velocity of 350 meters per second, the bullet would drop about 0.1 meter, 10 centimeters at 50 meters range. The light tube might also be slightly misaligned and the laser light would spread over some area. But it should still have effective accuracy at 50 meters, if the laser has adequate light to be seen, particularly under sunlight.
This would be a war crime for military usage since the bullet is open ended. The idea would be to have it available only for police agencies to insure that police have an advantage in gunfights. In the U.S., the lunatic lobby would insist on everyone haveing access to them, which would really be a bad idea since it would make killings much easier.
The pistol would be more expensive and the bullets many times more expensive than conventional designs.
Tuesday, May 1, 2012
Titanic follies
F-35 shown obsolete on previous posts
For some reason an Australian with a lot of money is threatening to build a copy of the Titanic. There are immediate peculiarities in this. The first being that even with first class staterooms the Titanic's cabins did not all have private bathrooms. People then had different standards. Apparently he means the overall shape of the ship and the public spaces with the same arrangement of corridors, excepting steerage class.
The ship will undoubtedly have diesel engines. The Titanic, as built, had 4 funnels, but only 3 were functional. The 4th was added to make the ship look more balanced. In the replica 33 out of 4 would be useless deadweight. They were also built tall to disperse coal ash, which is unnecessary with diesel fuel.
The Titanic's rudder was undersized and it had a peculiar arrangement of 3 propellor shafts. Obviously, the copy would be built with 2 shafts and either 2 rudders or electric engines that can pivot.
The Titanic's bow was built with a straight stem, apparently insurance companies at that time insisted on it. Maybe that was supposed to minimize damage in collisions. The problem is that it produces a very strong singularity as the bow hits water, producing unneeded drag. A more angled
bow reduces the singularity as bow hits peaceful water and reduces fuel consumption.
It really was not much of a ship and there is no reasonable cause to copy it.
For some reason an Australian with a lot of money is threatening to build a copy of the Titanic. There are immediate peculiarities in this. The first being that even with first class staterooms the Titanic's cabins did not all have private bathrooms. People then had different standards. Apparently he means the overall shape of the ship and the public spaces with the same arrangement of corridors, excepting steerage class.
The ship will undoubtedly have diesel engines. The Titanic, as built, had 4 funnels, but only 3 were functional. The 4th was added to make the ship look more balanced. In the replica 33 out of 4 would be useless deadweight. They were also built tall to disperse coal ash, which is unnecessary with diesel fuel.
The Titanic's rudder was undersized and it had a peculiar arrangement of 3 propellor shafts. Obviously, the copy would be built with 2 shafts and either 2 rudders or electric engines that can pivot.
bow reduces the singularity as bow hits peaceful water and reduces fuel consumption.
It really was not much of a ship and there is no reasonable cause to copy it.
Saturday, April 28, 2012
Small recorders
F-35 shown obsolete on previous posts
Accidents involving small private planes are investigated but they do not have flight recorders like commercial aircraft. This makes the work of the accident investigators much more difficult.
A simple improvement would be to have a recorder about the size of a pack of playing cards attached to the plane's dashboard. It would have an ambient microphone to record conversation and general aircraft noises and three axis motion and rotation measurements/
It should cost only a few hundred dollars if built into s new plane and maybe a few thousand dollars to retrofit existing aircraft. It can be built much more simply than commercial aircraft recorders because the enery of ground collision is much less. The total fuel heating from fire would also be less and frequently small planes crash without burning. It could have a lithium battery to record after engine failure. The cost would be low because it would have no connections to the aircraft controls. This limits the amount of information gathered, but it would atill be a major improvement for accident investigators over currently having nothing.
Accidents involving small private planes are investigated but they do not have flight recorders like commercial aircraft. This makes the work of the accident investigators much more difficult.
A simple improvement would be to have a recorder about the size of a pack of playing cards attached to the plane's dashboard. It would have an ambient microphone to record conversation and general aircraft noises and three axis motion and rotation measurements/
It should cost only a few hundred dollars if built into s new plane and maybe a few thousand dollars to retrofit existing aircraft. It can be built much more simply than commercial aircraft recorders because the enery of ground collision is much less. The total fuel heating from fire would also be less and frequently small planes crash without burning. It could have a lithium battery to record after engine failure. The cost would be low because it would have no connections to the aircraft controls. This limits the amount of information gathered, but it would atill be a major improvement for accident investigators over currently having nothing.
Thursday, April 26, 2012
Scientific learning
F-35 shown obsolete on previous posts
One of the disappointments of engineering and science ids the refusal to use science to teach science. The claimed methodology of science is to create a model then measure and evaluate the model before continuing it or rejecting it. This is not done in instruction. Each instructor chooses to teach in any manner he desires with out regard to its results.
It would make more sense to test students as well as having them fill out surveys to determine satisfaction and assessment of knowledge gained. The next step is to promote the methods that work and discontinue the ones that do not. It might actually improve the efficiency of education.
It might not be possible or desirable to standardize across all curricula, there is too much diversity in student ability across schools and departments. But it should be possible over time within one school to evaluate and improve the methodology, and it might have some applicability to other schools.
A fair amount of variety in teaching methodology should be encouraged, but it must be evaluated and the better parts adopted generally.
One of the disappointments of engineering and science ids the refusal to use science to teach science. The claimed methodology of science is to create a model then measure and evaluate the model before continuing it or rejecting it. This is not done in instruction. Each instructor chooses to teach in any manner he desires with out regard to its results.
It would make more sense to test students as well as having them fill out surveys to determine satisfaction and assessment of knowledge gained. The next step is to promote the methods that work and discontinue the ones that do not. It might actually improve the efficiency of education.
It might not be possible or desirable to standardize across all curricula, there is too much diversity in student ability across schools and departments. But it should be possible over time within one school to evaluate and improve the methodology, and it might have some applicability to other schools.
A fair amount of variety in teaching methodology should be encouraged, but it must be evaluated and the better parts adopted generally.
Tuesday, April 24, 2012
Army cargo
F-35 shown obsolete on previous posts
The movement of logistics is the first challenge of modern militaries. The use of containers had revolutionized cargo movement, it could similarly change military logistics.
For military usage, containers could be built each of which would be 1/3 the length of a standard container. 3 of them could be clamped together and shipped and moved as a standard container. On arrival at the destination shipping port, they would be separated and placed on a 5 ton truck for resupplying forward units.
A standard container is 8 feet wide and 9 feet high. For military usage, they would be 8 feet wide and 6 1/2 feet high, allowing an internal height of 6 feet, the remainder being structure. It would be a bit of a head knocker but soldiers wear helmets.
The advantage is that the packaging and sorting would be done in the U.S., simplifying logistics and allowing fewer logistic personnel being needed at the forward location.
The one one drawback is that the density of cargo might be lower to avoid overloading the truck. That would mean less cargo in each 3 set than a standard container, which would require more containers and more ships, although more containers could be shipped with each of lower height. The stacked height of containers,and the raised center of mass they create, limits container carriage on ships. Additionally, 4 cargo boxes rather than 3 could be in the length of 1 container rather than 3.
The other weak point is that the clamps must be highly reliable or there will be a significant risk of the boxes separating and being dropped when lifted by cranes.
For military usage, containers could be built each of which would be 1/3 the length of a standard container. 3 of them could be clamped together and shipped and moved as a standard container. On arrival at the destination shipping port, they would be separated and placed on a 5 ton truck for resupplying forward units.
A standard container is 8 feet wide and 9 feet high. For military usage, they would be 8 feet wide and 6 1/2 feet high, allowing an internal height of 6 feet, the remainder being structure. It would be a bit of a head knocker but soldiers wear helmets.
The advantage is that the packaging and sorting would be done in the U.S., simplifying logistics and allowing fewer logistic personnel being needed at the forward location.
The one one drawback is that the density of cargo might be lower to avoid overloading the truck. That would mean less cargo in each 3 set than a standard container, which would require more containers and more ships, although more containers could be shipped with each of lower height. The stacked height of containers,and the raised center of mass they create, limits container carriage on ships. Additionally, 4 cargo boxes rather than 3 could be in the length of 1 container rather than 3.
The other weak point is that the clamps must be highly reliable or there will be a significant risk of the boxes separating and being dropped when lifted by cranes.
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