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>You lose on range (~20 miles max) Just because it's still a super cool feat 17 years later, from 2003: https://www.sciencenewsforstudents.org/article/model-pl

by xoa 7y ago

>You lose on range (~20 miles max) Just because it's still a super cool feat 17 years later, from 2003: https://www.sciencenewsforstudents.org/article/model-plane-flies-atlantic https://www.sciencenewsforstudents.org/article/model-plane-f... >11-pound Model Airplane Flies the Atlantic >Named TAM-5, the 11-pound plane flew 1,888 miles from Canada to Ireland in 38 hours, 53 minutes. It set world records for longest distance and longest time ever flown by a model airplane. >[...]To qualify for flight records, a model airplane has to weigh less than 11 pounds, including fuel. So, TAM-5 had room to carry just under 3 quarts of gas. This meant that the plane had to get the equivalent of about 3,000 miles per gallon of fuel, Brown says. >The biggest challenge in building the model, Brown says, was figuring out how to make TAM-5’s engine efficient enough to cross the ocean. Most model airplanes use alcohol-based fuels. Instead, Hill used Coleman lantern fuel because, he says, it’s more pure and performs better. He tweaked a regular model airplane engine to make the valves smaller and more efficient. >The plane also carried an impressive set of electronics. Every hour during the flight, crewmembers were able to get information about the plane’s location from a Global Positioning System (GPS) device on board. The GPS device communicated with a satellite orbiting Earth to determine the plane’s exact latitude, longitude, and speed. >The route was programmed into the computerized autopilot, which automatically adjusted the plane’s direction to stay on course. There was also a transmitter on board that sent signals directly to crewmembers on the ground when the plane was within 70 miles of its launch and landing sites. So that's 2003-class "impressive set of electronics", with artificial fuel restrictions for record purposes to boot, yet nearly a couple thousand miles of range. Only going about 50 MPH granted, but presumably a weaponized design would only need to burst speed briefly and slow loiter might actually be a strength in some CAS scenarios. Napkin math'ing it, seems feasibly dangerous, 3 US quarts of kerosene is about 5 lbs and a couple lbs of shaped RDX is plenty to do some real damage if a pinpoint strike. Just saying that I think you're even more right than you suggest there! A scenario of fielding thousands/tens of thousands of cheap drones offers chances for a pretty radical rethink in doctrine.

user5994461 7y ago
Interesting read, although the derived applications are not great. ^^ Now for more military applications, I think some of the calculations might break down due to weight. Missiles/shell can be in the order of hundreds of pounds, with the heavier ones above a ton. The use case for military being more oriented toward heavy vehicles, tanks and buildings, I don't think a few pounds of explosive would be anywhere near enough. The plane would have to increase in size (structure and fuel) in similar proportions to the load it has to carry, certainly negating a lot of the efficiency. Well, if we streamline a model plane as a one off directed explosive, that will eventually be a missile and long range ballistic missiles are not a novelty.
- nostrademons 7y ago
  > The use case for military being more oriented toward heavy vehicles, tanks and buildings, I don't think a few pounds of explosive would be anywhere near enough. That describes a bazooka warhead perfectly, and they had no problem penetrating tanks. More recently, TOW anti-tank missiles are used to great effectiveness by many armies (including us) and their warhead is only 13 lbs. One of the amazing things about shaped charges is that penetration depends only on the diameter of the charge, not its weight or velocity, and it can penetrate 7-10x its diameter in armor. So a 4-inch diameter shaped charge can blow through a meter of solid steel. The other interesting development is that nearly all the advances in armor designed to defeat shaped charges (ceramics, Chobham armor, reactive armor) have an assumption that the same spot will never be hit twice in battle. The first shot basically destroys the (roughly 1 sq. foot) armor tile, which is useless for further protection, but this doesn't matter because in a traditional gun/missile tank duel the chance that the exact same spot will be hit twice is miniscule. This assumption falls apart with advances in robotics and AI. You could imagine a drone swarm where instead of launching themselves at the target, they land on the target, crawl to the most vulnerable parts (on top of turret or on the magazines/engines, for example) or those that have sustained previous battle damage, and then detonate themselves.
  - user5994461 7y ago
    Awesome, I thought of shaped charges as well, but trying to keep the post short. I assumed the goal was to have something similar to the model plane and particularly its incredibly range and efficiency. 1 gallon for 1000 miles. The plane shape and aerodynamics certainly help the efficiency. However if there was an explosive charge to carry, the charge certainly can't improve the plane structure or aerodynamics (hence reducing the efficiency of the plane overall) and I'm not sure the charge could be shaped and mounted in the most optimal way (reducing the efficiently of the explosive itself). So while the model plane might be incredibly efficient at flying, I question whether it could be anywhere near as good for the new purpose.

by xoa 7y ago

user5994461 7y ago

Interesting read, although the derived applications are not great. ^^ Now for more military applications, I think some of the calculations might break down due to weight. Missiles/shell can be in the order of hundreds of pounds, with the heavier ones above a ton. The use case for military being more oriented toward heavy vehicles, tanks and buildings, I don't think a few pounds of explosive would be anywhere near enough. The plane would have to increase in size (structure and fuel) in similar proportions to the load it has to carry, certainly negating a lot of the efficiency. Well, if we streamline a model plane as a one off directed explosive, that will eventually be a missile and long range ballistic missiles are not a novelty.

nostrademons 7y ago
> The use case for military being more oriented toward heavy vehicles, tanks and buildings, I don't think a few pounds of explosive would be anywhere near enough. That describes a bazooka warhead perfectly, and they had no problem penetrating tanks. More recently, TOW anti-tank missiles are used to great effectiveness by many armies (including us) and their warhead is only 13 lbs. One of the amazing things about shaped charges is that penetration depends only on the diameter of the charge, not its weight or velocity, and it can penetrate 7-10x its diameter in armor. So a 4-inch diameter shaped charge can blow through a meter of solid steel. The other interesting development is that nearly all the advances in armor designed to defeat shaped charges (ceramics, Chobham armor, reactive armor) have an assumption that the same spot will never be hit twice in battle. The first shot basically destroys the (roughly 1 sq. foot) armor tile, which is useless for further protection, but this doesn't matter because in a traditional gun/missile tank duel the chance that the exact same spot will be hit twice is miniscule. This assumption falls apart with advances in robotics and AI. You could imagine a drone swarm where instead of launching themselves at the target, they land on the target, crawl to the most vulnerable parts (on top of turret or on the magazines/engines, for example) or those that have sustained previous battle damage, and then detonate themselves.
- user5994461 7y ago
  Awesome, I thought of shaped charges as well, but trying to keep the post short. I assumed the goal was to have something similar to the model plane and particularly its incredibly range and efficiency. 1 gallon for 1000 miles. The plane shape and aerodynamics certainly help the efficiency. However if there was an explosive charge to carry, the charge certainly can't improve the plane structure or aerodynamics (hence reducing the efficiency of the plane overall) and I'm not sure the charge could be shaped and mounted in the most optimal way (reducing the efficiently of the explosive itself). So while the model plane might be incredibly efficient at flying, I question whether it could be anywhere near as good for the new purpose.