History AwesomeButImpractical / Military

* The dreadnaught battleship HMS ''Agincourt'' was a ship that the Royal Navy didn't particularly want, but seized it to keep it away from another country, who bought it from a third. At the end of the 19th and early 20th centuries, [[https://en.wikipedia.org/wiki/South_American_dreadnought_race Chile, Argentina, and Brazil]] got into a naval arms race, each country buying battleships from foreign yards, as they couldn't build their own. Brazil, with plenty of cash from coffee and rubber plantations, ordered a ship from Armstrong Whitworth of [[UsefulNotes/NortheastEngland Newcastle]], with [[MoreDakka fourteen 12" guns]] in seven turrets (the most ever fitted to a battleship), partially in the spirit of this oneupmanship and to appear powerful to the Brazilian public. However, soon after this, the Brazilian economy took a sharp downward turn due to competition from rubber plantations in the Far East (planted by British companies, ironically enough) and Brazil sold the incomplete ship to the Ottoman Empire. The ship was actually completed and ready for delivery to her Turkish crew when UsefulNotes/WorldWarOne broke out, and the UK government seized the ship. This was actually a provision of the contract, but only if the UK was actually at war. First Lord of the Admiralty UsefulNotes/WinstonChurchill didn't want to take any chances and ordered the Turks held off by gunfire, if necessary, which turned Turkish public opinion against the British and [[NiceJobBreakingItHero contributed to them joining the Central Powers]]. Now named after a famous British victory over the French[[note]]and nicknamed "Gin Palace" after the luxurious fittings the Turks requested and her name being [[IncrediblyLamePun A Gin Court]][[/note]], she was put into the Grand Fleet, where her shortcomings became apparent. Her firepower was so impressive that a full broadside completely hid the ship in flames and smoke, but to protect all those turrets and their magazines required the armoured belt to be unusually long, and thus it was unusually thin to keep the weight down. Barbette and deck armour was also thin compared to other dreadnaughts, making her something of a GlassCannon. And for all that, she participated in only one major battle, at Jutland, where poor visibility meant she fired 144 12" shells and 111 6" shells, but never hit anything.

* The Messerschmitt Me-262 Schwalbe, the world's first operational jet fighter. While fast enough to leave any Allied plane in its contrails and an excellent bomber interceptor, its engines were prone to mechanical problems and required high temperature alloys that Germany didn't have enough of. It also required more fuel than the Germans could afford to ration to it. Many armchair historians have cited UsefulNotes/AdolfHitler's decision to make the 262 a fighter-bomber as a boneheaded move that delayed the introduction of a potentially war-winning weapon, but this view is mistaken and unrealistic: Hitler was right in believing that the 262 would be the only aircraft capable of penetrating the air umbrella over an Allied invasion fleet, though it wasn't ready in time, and the fighter-bomber issues only delayed production by about a month. And by that point in the war ''all'' fighters were effectively fighter bombers, as the Allies realized that fighters made effective ground attack aircraft and used them to replace dead-end types like dive bombers. The fact of the matter is that the Germans rushed the 262 into service about as fast as they could have, and its premature birth was part of the reason for its problems. Finally, even if it had gone straight to fighter units, their primary opponents - the P-51 Mustang and the Supermarine Spitfire - still would have outnumbered them 60 to 1.

* The [=XM29=] OICW. It was a standard 5.56mm assault rifle with a 20mm grenade launcher that had programmable airburst grenades. Issues came about due to weight,[[note]]the target weight was 15 pounds, three heavier than the existing [=M16A2=] with M203 combination; the actual weight ended up being 18[[/note]] cost,[[note]]Whereas the [=M16A2=] and M203 cost $1,000 together, the projected cost for the full [=XM29=] was $10,000 per unit, and the actual cost was likely to be $35,000 at minimum, to say nothing that each 20mm grenade for the launcher cost $150, versus a regular 40mm grenade only costing $8; the only reason the regular bullets didn't cost more was that those were the same as with the M16[[/note]] and the ineffectiveness of both the 20mm grenade[[note]]it was too small for proper [[NonFatalExplosions lethal]] air-bursting or fragmentation[[/note]] and the rifle itself compared to the [=M16A2=][[note]]thanks to a barrel just barely longer than nine inches, which wasn't enough to generate an effective muzzle velocity for bullets to go where they were actually aimed or particularly damage what they did hit. The [=M16A2=]'s 20-inch barrel is generally considered to be ideal for maximizing the 5.56x45mm cartridge's lethality; anything shorter than the M4 carbine's 14.5-inch barrel - and for the record, no other military AR-15 derivative has gone below ten and a half inches - is intended for a role similar to submachine guns rather than a normal rifle.[[/note]].
** The grenade launcher part did manage to spawn the [=XM25=], using a larger and more effective 25mm grenade, which saw continued testing and some actual service. Unfortunately, the [=XM25=] would also fall victim to this trope. Despite its original design as something that would later be recombined with the concurrent [=XM8=] rifle to give another shot at the full OICW package, the [=XM25=] and its ammunition were rather heavy, forcing the user to forego a rifle. This reduced their combat effectiveness, since it limited their close-range combat capabilities, along with its lower overall ammunition capacity. The air-bursting grenades were quite expensive, even moreso than the [=XM29=]'s at $1000 per round. Eventually, [=40mm=] grenades were developed with air-bursting capability, which were much cheaper and more standardized than the [=XM25=]'s specialized [=25mm=] rounds and following lawsuits between the people who were supposed to produce the weapon, the project was finally canned in 2018.

* The Spanish ship Nuestra Señora de la Santísima Trinidad (''Our Lady of the Holy Trinity''), a ship larger than the already massive first-rate ship of the line. For comparison, here is [[http://www.hnsa.org/ships/img/victory1.jpg HMS Victory.]] The Santísima Trinidad carried 140 guns, compared to HMS ''Victory's'' 104. It was so huge that it crawled at a snail's pace (and was nicknamed ''el Ponderoso'' (The Ponderous) as a result). So many men were required to man it that its supplies ran out very quickly unless it was near a friendly port. The Santísima Trinidad only saw battle twice: Cape St Vincent, where it ended up surrendering without doing any damage, but the Spanish ships ''Infante Don Pelayo'' and ''Príncipe de Asturias'' managed to reach and secure her before the British, and [[CurbStompBattle Trafalgar]], where it was battered into surrender by the more maneuverable HMS ''Neptune'' and then later scuttled by the British in a storm due to its high center of gravity. It was Awesome, But Impractical incarnate.
** The US Navy had the USS ''Pennsylvania'', a four decker of 140 guns and physically larger than the ''Santisma Trinidad''. It was authorized in 1816, laid down in 1821, and... launched and commissioned in 1837. The HMS ''Victory'', for comparison, took only six years to complete (then spent twelve years in ordinary until finally commissioned during the Revolutionary War), while the HMS ''St Lawrence'', of 112 guns and the only first rate in the Great Lakes, was laid down in April 1814 and completed and commissioned in ''September 1814''.[[note]]Despite the extravagance involved in building a first rate ship of the line to fight on a '''lake''', and the fact that ''St Lawrence'' never saw combat, she was arguably not an example of this trope. The reason she never saw combat was that no US Navy ships dared to set sail on the Great Lakes for the remainder of the War of 1812, lest they have to face such a powerful ship.[[/note]] The ''Pennsylvania's'' only voyage was in 1837-8, from Delaware Bay to Chesapeake Bay, and was finally burned in 1861 to prevent her capture by the Confederates.

** Even if they hadn't been rendered obsolete by airpower, ''Yamato'' and ''Mushashi'' defined the ragged outer edge of practicality for battleships. Manufacturing their armor pushed the limits of the Japanese steel industry. The maximum range of their guns exceeded the distance that any naval gun could be aimed accurately. The sheer size of their guns required the Japanese to invent an entirely new technology in materials handling equipment just to move the projectiles around the magazines. The extreme weight of their turrets exceeded the metallurgy available for their supporting bearings. And finally their price tags were so extreme the cost to construct them actually damaged the national economy. Finally their actually performance in operation makes a pretty convincing demonstration that the even bigger battleships planned by the Japanese and the Germans simply wouldn't have worked.

* Ladies and gentlemen I present to you [[https://museum-of-artifacts.blogspot.com/2015/10/joseph-enouys-8-cylinder-48-shot.html?m=1 the Enouy revolver.]] A revolver with eight cylinders that could fire 48 shots. As a surprise to no one the gun is unwieldy, unbalanced and heavy.

* Conceived in a post-Cold War environment, the Littoral Combat Ship (LCS) program was intended for the US Navy to produce smaller ships that would solve the Navy's deficiency in asymmetric costal combat, resulting in the ''Freedom'' and ''Independence’’-class ships. Each LCS vessel has many features to provide top-tier combat for lower costs like stealth abilities, automated systems to reduce crew size and swappable modular packages that could reconfigure each ship for any role on a short-notice. However, the LCS fell victim to feature creep that resulted in cost overruns and technical problems. Many modular packages like the unmanned de-mining and anti-submarine suites were unreliable and altogether costed over $7 billion, leading to the Navy abandoning the system. Likewise, the automation system proved inadequate for long-term operations, resulting in an overworked and understaffed crew. Additional trials showed numerous design problems in each ship like the ‘’Freedom’’ having problematic engines and the ''Independence’’ having cracking hulls. In hindsight, LCS was too costly and complicated for a specialized role that could've been filled by a cheaper, more proven design like the Visby-class corvettes.

*** On paper it looks like the best fighting tank in the war: it had better mobility, frontal armor, and gun performance against tanks than the Tiger I, yet it was far cheaper and produced in quantity second only to that of the Panzer IV. On the other hand it was somewhat over-specialized for Eastern-style long-range combat on open ground, leading to some design choices that would be rather problematic in the closer quarters of the Western front: the commander didn’t have a turret traverse override to help the gunner get on target, while the gunner had no periscope or unity sight, just the magnified gunsight through the mantlet which had restricted field of view. If the tank was in a turret-down position, or if the enemy happened to not be within the sight picture already, the gunner has nothing to go on except the commander’s verbal instructions, reducing "shoot first" capability and making it more awkward at closer ranges. The turret traverse speed was also slow, putting it at a disadvantage if the enemy approached from an unexpected direction. Despite being lighter than the Tiger, the Panther still had to beware of crossing bridges or breaking the final drive by performing high-torque maneuvers such as pivot turning. There were also some weaknesses in protection: it had thin side armor because of the need to keep weight under control, and the ammo racks were in the hull sponsons where they could get hit and catch fire. Probably the worst oversight was that the curved underside of the gun mantlet could act as a shot trap by deflecting an incoming shell downwards into the thinly-armored front hull roof, one of the few frontal weaknesses that a 75 mm Sherman could exploit.

** However, the R35 and H35 which were the most numerous models had painfully low horsepower, and were armed with weak, short-barreled 37 mm SA 18 cannons taken straight off of old World War I [=FTs=]) that could penetrate only about 20 mm of armor. They had been designed as infantry tanks that would replace the old FT, hence the lack of concern about speed or anti-tank capability. The R35 showed the teething problems of early hull casting technology, as the steel came out much weaker than its thickness would imply. Tests proved it was vulnerable not only to 25 mm antitank rounds, but even in some places to 8 mm armor piercing bullets.
** The FCM 36 two-man infantry tank was welded and angular in construction, because ''Forges & Chantiers de la Méditerrannée'' was a shipbuilding company. However, at this time welding was only done by skilled workers who required higher pay, and while the tank's welded construction was quicker than the alternatives of casting or riveting it also cost more. The welding technique was also imperfect, as the welds could burst if the tank was hit. When they tried to replace the underpowered SA 18 cannon with the more powerful SA 38, the turret welds couldn't handle the recoil. A new, strengthened turret for the SA 38 was not available in time for the German invasion. Of 400 orders for the FCM 36, only 100 were early enough to be built in time for the German invasion. They may have been the best of France's two man tanks on the whole, since they had sloped armor, a reliable diesel powertrain, and a turret less cramped than the APX (which is what the next bullet is about), but with too many of the same vision and crew comfort problems as the others it just wasn't better ''enough'' to be considered good.

*** Now, despite its faults, Nicholas Moran [[https://youtu.be/57oRqB_a-SA notes]] that on the whole it was actually a pretty excellent tank; the problem is that it was designed to perform a specific role, and then it was yanked out of that role by circumstance. The Tiger was an elite heavy breakthrough tank meant to punch a hole in the enemy's line, which exploitation forces with cheaper tanks would then flood through. At that point the Tiger's job would already be done, and it could be withdrawn for maintenance and repairs to await its next mission. It wouldn't have been such a problem that it took more logistics and planning to transport, or that it took more man-hours to maintain, because that kind of breakthrough task wouldn't be demanded very often and there should have been plenty of time between missions to take care of those matters. The Tiger's high cost and low numbers were also acceptable to the Wehrmacht because it was never intended to replace standard medium tanks, but rather to support the military's panzer forces in an important specialized role. Unfortunately, when the invasion of Russia turned into a fiasco, desperate German commanders who were often ignorant of the Tiger's limitations turned it into what Moran calls "The Fireman of the Eastern Front": wherever the Soviets attacked German forces the Tigers would be rushed over there to defend, and no sooner had they put out the fire in one place then they would be on their way to extinguish another somewhere else. This lack of rest meant they couldn't take the the proper time for repairs or maintenance, and with ever more breakdowns the operational readiness rate of Tigers went way down, so that there often wouldn't be enough in working order when they were really needed. Maybe this tank could have been just plain awesome in the proactive role its was designed for, but it turned out impractical in the reactive role that was forced upon it.

*** On paper it looks like the best fighting tank in the war: it had better mobility, frontal armor, and gun performance against tanks than the Tiger I, yet it was far cheaper and produced in quantity second only to that of the Panzer IV. On the other hand it was somewhat over-specialized for Eastern-style long-range combat on open ground, leading to some design choices that would be rather problematic in the closer quarters of the Western front: the commander didn’t have a turret traverse override to help the gunner get on target, while the gunner had no periscope or unity sight, just the magnified gunsight through the mantlet which had restricted field of view. If the tank was in a turret-down position, or if the enemy happened to not be within the sight picture already, the gunner has nothing to go on except the commander’s verbal instructions, reducing "shoot first" capability and making it more awkward at closer ranges. Despite being lighter than the Tiger, it still had to beware of crossing bridges or breaking the final drive by performing high-torque maneuvers such as pivot turning. There were also weaknesses in protection: it had thin side armor because of the need to reduce weight, and the ammo racks were in the hull sponsons where they could get hit and catch fire. The curved underside of the gun mantlet could act as a shot trap by deflecting an incoming shell downwards into the thinly-armored front hull roof, one of the few frontal weaknesses that a 75 mm Sherman could exploit.

** Pull up a chair and read the saga of the Tiger I that ''didn't'' get made, and instead became Germany's worst AFV in World War II:

* In the 2000s, the Navy initiated the Littoral Combat Ship (LCS) program to create a ship that would solve their deficiency in asymmetric costal combat, resulting in the ''Freedom'' and ''Independence’’-class ships. Each LCS vessel has many features to provide top-tier combat for lower costs like stealth abilities, automated systems to reduce crew size and swappable modular packages that would reconfigure each ship for any role on a short-notice. However, the LCS fell victim to feature creep that resulted in cost overruns and technical problems. Many modular packages like the unmanned de-mining systems and anti-submarine suite were unreliable and costed over $7 billion, leading to the Navy abandoning it. Likewise, the automation system proved inadequate for long-term operations, resulting in an overworked and understaffed crew. Additional trials showed numerous design problems in each ship like the ‘’Freedom’’ having problematic engines and the ''Independence’’ having cracking hulls. In hindsight, LCS was too costly and complicated for a specialized role that could've been filled by a cheaper, more proven design like the Visby-class corvettes.

* [[FirebreathingWeapon Flamethrowers]]. It was an ideal weapon for WWI and WWII that could quickly torch infantry, bunkers, and vehicles while also having the psychological effect of producing the hellish images of burning people screaming in pain. However, the weapon was eventually phased out since the Vietnam War for several reasons. First, it was a heavy weapon that weighed down the user and turned them into a highly visible target. Second, while its range isn't as [[VideoGameFlamethrowersSuck atrociously short as depicted in the media]], it still wasn't effective for long range engagements. Third, the weapon couldn't be safely stored in such a way that it would not explode if hit by an explosive or incendiary projectile. Finally, even its psychological advantage has its own downside; since flamethrowers were so terrifying, their users were always the first to get targeted. Incendiary rockets and grenades have since been tried as more practical alternatives, although some of these have their own problems.

* The immediate predecessor and the rifle the M16 replaced, the M14, was also an example of this. The M14 was a far more traditional rifle than the M16, with a body made of wood, mechanisms based on the M1 Garand rifle and firing a full-sized rifle round (the NATO-standard 7.62x51mm round, which matched the ballistics of the prior .30-06 Springfield round in a slightly smaller and lighter package). Unlike the Garand, it was selective-fire and could fire on full auto as well as semi-auto. The idea of the rifle was to replace several semi- and fully automatic weapons systems with a single do-all weapon that could reliably engage a target at any possible range. The fact that it was a more "traditional" rifle compared to the M16 also meant it was more widely accepted by the old guard of the U.S Military in its approach of emphasizing the role of individual riflemen over everything else. However, it proved to be very flawed as a general infantry weapon. For starters, the M14 is two pounds heavier than an M16. Its ammunition was also heavier than an M16's, with the same amount of ammo becoming a much greater burden for a soldier trudging through Southeast Asia. The heavier round also resulted in heavier recoil, which made the M14 extremely inaccurate in sustained automatic fire (this trend had been discovered earlier by the Russians when they tested the AVS-36, one of Simonov's first automatic rifles, way back in the 1930s - the problem turned out to be that the ergonomics of semi-pistol-grip weapons like these simply aren't designed to keep on target at 700 rounds per minute). Finally, [[JackOfAllTrades in attempting to be a do-all weapon system]], it had [[MasterOfNone failed to surpass any of them]]. It was too light to be a squad automatic weapon, too heavy to be comparable to a submachine gun and one Department of Defense report went so far as to call it "completely inferior" to the M1 Garand. The only real improvement was that it used a detachable 20-round magazine instead of feeding from 8-round clips like the M1... and John Garand had already designed a modified M1 using BAR magazines of that capacity before anybody thought of the M14. He called the M14's gas system 'junk'. Most damning, Springfield Armory could neither produce it in the numbers needed for mass adoption (breaking one of the promises that had effectively sold the weapon over the FN FAL and thus gave the Pentagon the excuse it needed to not buy a foreign rifle; it took seven years before the change to the M14 was completed) nor use the existing production tooling for the M1 (the other promise that sold it over the FAL), since, even if that had been possible (the design turned out to be just different enough that it couldn't be made on existing Garand tooling), it had all either been broken beyond repair or sold off to Italy. To add insult to injury, the Italian firm Beretta actually designed [[https://en.wikipedia.org/wiki/Beretta_BM_59 a comparable battle rifle]] that ''could'' be manufactured with the original M1's tooling. Eventually, the M14 was completely replaced as a frontline general-issue infantry weapon. It was however later modified into several designated marksman's rifles like the M21, a role it has proved to be much more capable in.

* The immediate predecessor and the rifle the M16 replaced, the M14, was also an example of this. The M14 was a far more traditional rifle than the M16, with a body made of wood, mechanisms based on the M1 Garand rifle and firing a full-sized rifle round (the NATO-standard 7.62x51mm round, which matched the ballistics of the prior .30-06 Springfield round in a slightly smaller and lighter package). Unlike the Garand, it was selective-fire and could fire on full auto as well as semi-auto. The idea of the rifle was to replace several semi- and fully automatic weapons systems with a single do-all weapon that could reliably engage a target at any possible range. The fact that it was a more "traditional" rifle compared to the M16 also meant it was more widely accepted by the old guard of the U.S Military in its approach of emphasizing the role of individual riflemen over everything else. However, it proved to be very flawed as a general infantry weapon. For starters, the M14 is two pounds heavier than an M16. Its ammunition was also heavier than an M16's, with the same amount of ammo becoming a much greater burden for a soldier trudging through Southeast Asia. The heavier round also resulted in heavier recoil, which made the M14 extremely inaccurate in sustained automatic fire (this trend had been discovered earlier by the Russians when they tested the AVS-36, one of Simonov's first automatic rifles, way back in the 1930s - the problem turned out to be that the ergonomics of semi-pistol-grip weapons like these simply aren't designed to keep on target at 700 rounds per minute). Finally, [[JackOfAllTrades in attempting to be a do-all weapon system]], it had [[MasterOfNone failed to surpass any of them]]. It was too light to be a squad automatic weapon, too heavy to be comparable to a submachine gun and one Department of Defense report went so far as to call it "completely inferior" to the M1 Garand. The only real improvement was that it used a detachable 20-round magazine instead of feeding from 8-round clips like the M1... and John Garand had already designed a modified M1 using BAR magazines of that capacity before anybody thought of the M14. Most damning, Springfield Armory could neither produce it in the numbers needed for mass adoption (breaking one of the promises that had effectively sold the weapon over the FN FAL and thus gave the Pentagon the excuse it needed to not buy a foreign rifle; it took seven years before the change to the M14 was completed) nor use the existing production tooling for the M1 (the other promise that sold it over the FAL), since, even if that had been possible (the design turned out to be just different enough that it couldn't be made on existing Garand tooling), it had all either been broken beyond repair or sold off to Italy. To add insult to injury, the Italian firm Beretta actually designed [[https://en.wikipedia.org/wiki/Beretta_BM_59 a comparable battle rifle]] that ''could'' be manufactured with the original M1's tooling. Eventually, the M14 was completely replaced as a frontline general-issue infantry weapon. It was however later modified into several designated marksman's rifles like the M21, a role it has proved to be much more capable in.

* The M16, when first used in Vietnam, was supposed to represent the pinnacle of the modern assault rifle. It was made of lightweight polymers which reduced the rifle's weight tremendously while still giving the user the option of automatic or single shot fire, decent penetration for its weight, and a number of other features which are now standard design elements. However, cost-cutting measures[[note]]Particularly the removal of chrome-plating in the bore. However, considering the fact that the versions without the chrome-plating were also the ones with the fairly pointless forward-assist added, which the Air Force, Colt, and Stoner all felt was a needless expense but the Army insisted on adding, this may or may not have been outright sabotage by members of the Army brass still bitter over having to replace the M14[[/note]] and a supply issue with the powder used with the ammunition it was tested with and designed for led to a switch late in the game that led to corrosion and jamming issues in the field. To make matters worse, the M16 had been issued without a cleaning kit[[note]]Or instructions on how to clean it, because apparently someone assumed that Colt saying it required very little maintenance and that the gas system was self-cleaning meant that it required ''no'' maintenance and the ''entire weapon'' was self-cleaning. Again, this may have been deliberate sabotage[[/note]]. While quickly fixed (as in by 1968) by the improved [=M16A1=], and evolving into a top-class assault rifle in the [=M16A4=], [[NeverLiveItDown the reputation lingers]], particularly among those that have [[ArmchairMilitary never used one]].

* Laser weapons struggle to find use outside of point defense systems on naval ships and stationary bases. Compared to conventional projectile weapons, lasers have a lower cost per shot, don't require carrying warheads or propellant charges that can cause catastrophic explosions if hit, and can instantaneously hit fast-moving targets because they travel at the speed of light. However, a power plant to supply the necessary amount of electric current is too large and heavy to be carried by a single person or installed in most aircraft or ground vehicles- as a result, such installations can only be found a ship (which are large enough to have the internal volume to justify said large powerplant) or a land base (which doesn't have to worry about powerplant size or weight) . Furthermore, while lasers can easily melt fragile equipment (such as drones, missiles and planes), a laser needs to shoot at one spot continuously for a long time to burn through hardier targets like bunkers and tanks. That requires the user to spend a longer time exposed to attack, and exacerbates the already-high energy consumption. Even worse is that aerial debris like dust, sand and smoke can block laser beams. So while laser weapons may have advantages in point defense against airborne threats, they're not yet powerful or adaptable enough to serve as a primary offensive armament against surface targets.

* [[ItsRainingMen Paratroops]] in general. True, they are the cream of the crop in each and every army, provide a potentially unexpected avenue of attack, and jumping out of a perfectly good plane mid-air is just plain awesome. However, paratroops suffer from a number of downsides. First, unless the drop zone is secured, the jump planes are easy to shoot down and the descending paratroopers are similarly vulnerable to ground fire. Second, paratroops are generally unsupported by heavy weapons such as artillery and armored vehicles, which cannot be easily carried by planes and are ''very difficult'', if not downright impossible, to safely drop by parachute. Third, parachute operations are heavily dependent on the element of surprise: once deployed, the paratroop is at a disadvantage, as their opponent can call for more firepower and reinforcements. Fourth and finally, if the paratroop cannot link up with friendly forces in a timely manner, then it will eventually run out of supplies, at which point surrender is the only rational option. The experience of WWII paradrop operations was that large scale paradrops usually fail (Market Garden is an obvious example) and even successful ones (Normandy, Crete and Operation Varsity) are costly, and typically only succeeded because the regular armies were able to arrive and reinforce them within a few hours to a day at most, but small scale operations (up to company level) usually succeed (an example would be the POW rescue in Los Baños). Helicopters have more or less superseded both gliders and paratroops in most armies around the world.

* So far as logistical prowess is concerned, the idea of a universal service cartridge sounds awesome, but has proven to be troublesome. The idea is to give every serviceman the exact same primary weapon ammunition for vastly different roles. The problem is that there are roles with vastly different requirements, so making a universal cartridge doesn't work out too well in the long run (you could change powder loads and projectile properties, but that undoes the whole "universal" idea).
* Laser weapons struggle to find use outside of point defense systems on naval ships and stationary bases. Compared to conventional projectile weapons, lasers have a lower cost per shot, don't require carrying warheads or propellant charges that can cause catastrophic explosions if hit, and can instantaneously hit fast-moving targets because they travel at the speed of light. However, a power plant to supply the necessary amount of electric current is too large and heavy to be carried by a single person or installed in most aircraft or ground vehicles; only a ship has enough internal volume and weight capacity to carry its own electric plant, while a permanent land base makes these non-issues. Furthermore, while lasers can easily melt fragile equipment (such as drones, missiles and planes), a laser needs to shoot at one spot continuously for a long time to burn through hardier targets like bunkers and tanks. That requires the user to spend a longer time exposed to attack, and exacerbates the already-high energy consumption. Even worse is that aerial debris like dust, sand and smoke can block laser beams. So while laser weapons may have advantages in point defense against airborne threats, they're not yet powerful or adaptable enough to serve as a primary offensive armament against surface targets.
* So far hypersonic missiles seem this way. While their extreme speed and unpredictable flight path makes them near impossible for any existing defense system to shoot down and gives them superb range, once they hit their higher speed they're unable to follow sensor input to precisely hit a target. As a platform for short-range ballistic missiles it certainly works well, but against any kind of maneuvering target where the exact location is uncertain, it's unlikely to be an effective weapon, making it unlikely for them to render carriers obsolete just yet. Furthermore, a single hypersonic missile costs $50-100 million, more than 10 times that of a conventional cruise missile.

*** The Russian airdrop operation at the Hostomel Airport in the War of Ukraine 2022 demonstrated well that paratroops may be a thing of the past. The operation went ''terribly'' pear-shaped. The VDV suffered terrible losses, were unable to secure the drop zone and were practically wiped out by the Ukrainians.

* [[https://en.wikipedia.org/wiki/Hand_mortar The hand mortar]]. A combination between a small artillery piece and a blunderbuss- basically 16th century frag GrenadeLauncher. The awesome speaks for itself, particularly considering it showed up in an era where the average soldier was still armed with a spear or sword. The impractical part? If it malfunctioned, the grenade could detonate in the barrel, ruining the weapon and injuring (or even killing) the user. Given how often early firearms misfired, you can see why not many soldiers wanted to use one. On top of that, it didn't actually extend grenade range that much over simply throwing it (arguably not enough to make up for its huge reload time) and was limited to fist-sized grenades that were surprisingly weak (the projectile design being primitive and the only explosives available being black powder, with 1/3 the energy to weight ratio of modern hand grenade fillers).

* Battlecruisers were this when they first came out. Combining the speed of a cruiser with the firepower of a battleship, they were designed to hunt down enemy cruisers, and were effective in that role. Unfortunately, the combination of speed and firepower made it tempting to use them in place of battleships... a role which quickly exposed the light armor that enabled them to have that combination of speed and firepower. Such matchups were a case of GlassCannon versus LightningBruiser. The [[ExactlyWhatItSaysOnTheTin fast battleship]] solved this problem, but they were spectacularly expensive, even by battleship standards.

** The Big E was also the fastest carrier in the fleet. Which turned out to not be that useful, because few escort ships (even among the handful of nuclear-powered cruisers that the Navy used to have) were fast enough to keep up.

* The US Navy's ''Zumwalt''-class destroyer. It was optimized to provide coastal bombardment from over the horizon – and out of range of shore-based anti-ship missiles – as part of an emphasis on building littoral capability for a US Navy that had otherwise focused on oceanic combat. To accomplish this role, it was equipped with an Advanced Gun System, which would be cheaper than missiles, and a tumblehome hull to maximize radar stealth. Unfortunately, [[CripplingOverspecialization this all came at cost to its combat capabilities in other areas]], especially compared to the Arleigh Burke destroyer. Despite its larger size, the Zumwalt's tumblehome hull means that it carries fewer missile cells than the Burke. Its radar system and anti-submarine suites are optimized for littoral tasks but are less capable for blue-water operations, reducing their strategic capabilities. The stealth system was redundant since it's large profile and near-shore combat role makes it easy to track visually or by satellite imagery. Yet most crucially, its fire support role was rendered obsolete by the advent of longer-ranged coastal defenses. Even its AGS became useless as the long-range guided projectile the AGS was designed to fire got cancelled due to ballooning costs making them just as expensive as the missiles they were ''supposed'' to replace. Worse, the AGS is [[CripplingOverspecialization so specialized around those long-range guided projectiles that it can't use conventional NATO-standard 155mm artillery shells]]. Altering the guns to fire such readily available shells was deemed too expensive to be worthwhile, and thus ships hyper-specialized for gunfire support [[EpicFail no longer have guns that actually work at all]]. Seemingly the only reason, aside from the SunkCostFallacy, that the US Navy keeps these white elephants in service at all instead of cutting their losses and getting back the scrap metal value is that their engines can produce a lot more electrical power than other destroyers and cruisers. The Navy hopes that this will allow the now-useless AGS to eventually be replaced with [[MagneticWeapons large railguns]].

** Overall, massed bomber raids saw a downward trend in popularity after World War II--sure, it's one hell of a display of aerial might, with the potential to deliver tons of ordinance to a single strategic target and wreak absolutely demoralizing destruction, but the risks of sending so many planes and people into hostile territory almost guarantees crippling losses. With the advent of jet-powered aircraft which could fly higher and faster and carry more ordinance, along with unmanned delivery systems such as cruise missiles and drones, the need for strategic bombing began to peter out. Compounding this was the development of guided missiles, both of the ground and air-launched varieties, which would make target practice of a massed formation of big, ungainly aircraft. The most egregious, and arguably most modern example of this would be [[https://en.wikipedia.org/wiki/Operation_Rolling_Thunder Operation Rolling Thunder]], which essentially was Awesome, But Impractical brought to life--mass bombing reminiscent of those seen in World War II, but with modern jet aircraft, SAM systems, supersonic dogfights, and more than ''1 million tons'' of bombs dropped--which is almost ''half'' of the total amount of ordinance dropped during the '''''entire European Theatre of World War II.''''' Despite this, losses continued to mount as the China-supplied North Vietnamese stubbornly resisted the bombing raids, to the point that the operation was cancelled in 1968.

* The Northrop Grumman B-2 Spirit heavy strategic bomber was the culmination of decades of research into stealth and precision bombing: It's a flying wing with no tail or fuselage, the engines and armament are hidden inside the wing/body, and every angle and curve was designed with the help of computers to deflect radio waves away from radar receivers below the bomber. The skin is made of materials that absorb radio waves and convert them into heat, and the engines have a low thermal signature. The intended capability was to slip through dense anti-aircraft defenses to deliver nuclear weapons. Then it suddenly lost much of its value as a strategic stealth bomber when the Soviet Union collapsed in 1991. It has since been relegated to rear echelon status and has seen action as a conventional bomber in only four conflicts: Kosovo, Afghanistan, the 2nd Gulf War, and the Libyan Civil War. On the plus side it performs conventional bombing very well, with an absolutely absurd bomb capacity, a varied arsenal of smart munitions that it can pick out of a revolver-like bomb bay carousel, and fantastic range thanks to its flying wing design. In particular, its ability to get very close before it shows up on radar helps it to slip through gaps in ground-based anti-air radar networks and bomb them, in order to clear the way for non-stealthy aircraft to come in and wreak havoc. However, there's still the problem that it's incredibly expensive to manufacture and maintain with each plane costing over ''$1 billion'', needing their own specialized climate-controlled hangars to maintain its stealth coating and requiring 50 hours of maintenance for every hour spent flying. It also requires a computer-controlled fly-by-wire system to safely operate the complex system of split-brake rudders, differential engine thrust, and "elevons" that control the inherently unstable flying wing aircraft, and if those computers fail the damn thing ''will'' crash.

* Among nuclear weapons, atomic bazookas are the least useful and most hazardous. During the 1950s the United States invented with the Davy Crockett recoilless rifle to fire low-yield nukes (think the Fat Man launcher from ''VideoGame/{{Fallout}}'' and you get the picture). As cool as the idea of a man-portable nuke may seem, it was rendered useless by the fact that the weapon's nuclear fallout radius was wider than its optimum firing range. So, it essentially it becomes a suicide weapon as the user would die from radiation poisoning after using it. Fortunately, it was never used in combat since it would probably inflict more harm on its users than its target.

* The Karl Device. [[https://en.wikipedia.org/wiki/Karl-Gerat Have a look]]. The second largest calibre weapon ever fired in war, one shell weighed two tons, and each launching platform weighed 124 tonnes. Could only be effectively moved by rail, and was almost useless as tactical weapon. But ''two tonnes'' of explosives.
** Here is what it looked like when it hit the [[https://en.wikipedia.org/wiki/File:Warsaw_Uprising_-_Prudential_Hit_-_frame_2a.jpg old offices of the Prudential Insurance Company]] in Warsaw. Here is a picture of a [[https://en.wikipedia.org/wiki/File:Warsaw_Uprising_by_Joachimczyk_-_Dud_in_Adria_-_459.jpg dud]] shell. One was also used during the Siege of Brest Fortress, where the shockwaves from the impact could travel through metres of concrete and still be lethal.

* In terms of airstrikes specifically, [[AirstrikeImpossible high risk, highly planned operations]] which use a large amount of aircraft tend not to produce worthwhile results due to the sheer fact that, as advanced and complicated as military aircraft are, the room for errors are ''incredibly'' small; as opposed to ground operations, where at least there is a ''chance'' to pull back and reconsider your options if something unexpected happens, in an air battle there is quite literally nothing between you and the enemy, with nowhere to hide. So, if something goes wrong, such as a premature loss of vital aircraft, unexpectedly heavy defenses, or unforseen changes in the weather the only option you have is to press the attack, follow the plan as best as you can, and ''hope'' things turn out okay. Such was the case of [[https://en.wikipedia.org/wiki/Operation_Tidal_Wave Operation Tidal Wave]], where the precise, low-level multi-squadron airstrike on the Ploiești oil refineries went to all hell due to a combination of mechanical failures, breakdowns in communication, and unexpected defenses that rendered the high-stakes operation AllForNothing with heavy casualties and no lasting effect on the refineries themselves. Of course if you want something of a more modern area, refer to the abortive [[https://en.wikipedia.org/wiki/Package_Q_Strike Package Q]] operation, which, like Tidal Wave, saw several separate failures pike up to ultimately render the entire mission useless, and which was later ''successfully'' completed by a smaller strike. When it comes to massed aircraft attacks, the simpler the operation, the better--for an Airstrike Impossible that ''did'' succeed, look at [[https://en.wikipedia.org/wiki/Operation_Catechism Operation Catechism,]] the operation to sink the German battleship ''Tirpitz''; the entire mission essentially boiled down to "get a shit-ton of [[BigBulkyBomb Tallboy]] Bombs, load them onto a squadron of Avro Lancasters (the only plane capable of holding said bomb), and ''[[ThereIsNoKillLikeOverkill bomb that fucking ship to kingdom come]].'' And hey, it worked!
** On the third try (after the failed operations ''Paravane'' and ''Obviate'') and mainly because ''Tirpitz'' was unable to move on her own power due to her destroyed engines. The Norwegians said ''Tirpitz lived a life of a loner and died a death of a cripple''.

** On the third try (after the failed operations ''Paravane and ''Obviate'') and mainly because ''Tirpitz'' was unable to move on her own power due to her destroyed engines. The Norwegians said ''Tirpitz lived a life of a loner and died a death of a cripple''.

* The [[https://en.wikipedia.org/wiki/Messerschmitt_Me_163 Messerschmitt Me-163 Komet]], designed by Alexander Lippisch and introduced in 1944, is the only rocket-powered fighter aircraft to have ever seen operational use. Its role was to be an interceptor which could rapidly engage enemy bombers by climbing to 12,000 meters (39,000 ft) in an then-unheard-of three minutes, and it could reach more than 1000 km/h (621 mph) in level flight, the first piloted aircraft to ever do so. However, there were a bunch of problems. First, the sheer speed and altitude. It flew so high without a pressurized cabin that pilots had to train for the brutal conditions in altitude chambers, and were required to eat a special low-fiber diet to reduce painful intestinal gas. It also flew so fast that they couldn't accurately hit slow-moving bombers with their low-velocity, short-ranged cannons: no pilot ever scored more than one victory with it. A promising solution to the high-speed targeting problem was a bank of ten single-shot, upwards-pointing cannons that would fire automatically when a photocell detected the silhouette of the bomber above it, but this came too late and was seemingly only used in combat once, on 10 April, 1945. Secondly, it burned up all its fuel in just seven and a half minutes, turning into an unpowered glider to get back to its airfield. This meant it could only be used for point defense, and rendered it helpless if the enemy decided to pick it off while it was gliding home. Thirdly, it was extremely unsafe for both pilots and ground crews. The rocket engine used two highly-corrosive chemicals called C-Stoff and T-Stoff, and created thrust by virtue of the fact that these substances were hypergolic, meaning they violently combusted upon mixing. Since these were both clear liquids that could be easily confused with one another, and were absolutely never supposed to come in contact with each other outside the engine, there were separate refueling teams for each fuel who were never allowed to be near the aircraft at the same time, and used different fueling ports on the plane. The fuel tanks and other systems would be regularly flushed out with water to prevent accidental explosions. However, even these measures didn't prevent occasional detonations on the tarmac. Moreover, the Komet had a habit of spontaneously exploding if jarred too much by, say, a rough landing, and the T-Stoff in particular was so toxic that a leak could kill the pilot even if there wasn’t an explosion. The plane was made of wood to keep the weight and cost down, and while it had wheels when it was going up, they broke away from the aircraft as it took off. What did you land with? ''A single skid''. The "best" part was that at this stage of the war, even flat runways were in short supply, so the pilots had to land them in bumpy, rocky fields. The whole idea was so poorly worked out that there were multiple incidents of these aircraft destroying themselves on takeoff '''with their own launch wheels'''. Because of the poor fields they were taking off from, it was entirely possible for the rubber-tired take-off wheel assembly to bounce higher than the altitude it was dropped from...and smash into the plane, often resulting in a catastrophic explosion. More pilots died trying to fly/land these things than in combat. Oh, and the engines were considered more valuable than the pilots. What does ''that'' tell you?
* Around the end of UsefulNotes/WorldWarII many rather impressive prototypes of fighter and bomber aircraft had been designed by various American and Russian manufacturers. Innovative uses of old technology (for instance, contra-rotating propellers) made them fast and powerful; sadly, the innovative use of ''new'' technology - namely the jet engine - resulted in aircraft that were even faster and more powerful, but also more efficient and less maintenance intensive. Needless to say, this doomed all the new piston-engine planes into never leaving the prototype stage.
** Related to the above is the turbo-compound engine. It was a late development that used a turbine placed at the end of the exhaust that would recycle power wasted by the piston engine and add it directly to the driveshaft. The engines thus obtained were very powerful and efficient, but were both maintenance-intensive and impractical: the bigger the turbine was the more efficient the engine became, until someone eventually figured out that you might as well leave the piston engine out altogether and simply use the turbine as a turboshaft.
*** The turbo-compound could make a comeback. The problem was it put a lot of stress on exhaust valves which would fail and their shards would take out the turbine. A lot of the power that could potentially go to the turbine was also absorbed by those valves. However, if used on a Wankel rotary engine, which has no exhaust valves, turbo-compounding could potentially make a Wankel engine that runs on automotive unleaded gasoline provide fuel economy and horsepower competitive with turboshaft engines, but without the turbo-lag.

** Her design doubles with DisasterDominoes, ExecutiveMeddling, UnitConfusion and HonorBeforeReason. After the catastrophe, a thorough investigation was held, and her five half-sisters were built with broader beam, more ballast, less armament and standardized Swedish (Stockholm) measurements. One of her half-sisters, ''Äpplet'' ("The Globus Cruciger"), which had been sunk as a blockship in 1660, was discovered in 2022.