For reasons of plot you have been given access to a time machine with instructions to help win the First World War for whichever side you choose.
Rules -
You can send back one weapon of your choice, but without an instruction manual or other information (ie: you can’t etch information onto it). This item will appear in a Terminator style manner (ie: dramatically) close behind your chosen sides front-lines and in a populated area so its likely that at least one soldier will see it arrive.
The item will have a small supply of ammunition, if you send something like an aircraft carrier back only the ship itself will arrive, not any of its attached aircraft.
Time of arrival will be shortly after things have settled into the stalemate trench warfare that will characterise the rest of the conflict.
The purpose is to win the Great War, any long-term consequences or after-effects not directly relevant to this goal will not count.
You have a competitor who is also sending a weapon back to their side, which will be the opposite of yours.
Can I send back brains? Because that seemed to be the thing most lacking in World War 1. And if you want to send brains in an equal measure to the other side, that would be fine.
Failing that, a bulletproof vest for the Archduke Franz Ferdinand. Make them come up with some other excuse to fight.
Given the restrictions set out in the OP, a nuclear bomb would probably be the only thing that would make a significant difference in actually changing the outcome. But with no knowledge on how they work there would be too great a chance it would be set off accidentally. My choice would therefore be to send an Abrams tank to the Allied forces so that tank warfare could could advance more quickly and end trench warfare that much sooner.
I’m going to amend my choice. An Abrams would be to advanced to be of much use to WWI era engineers. I think sending a WWII era T-34 to the Allies would probably be a bigger help.
Good timing, I’ve just started John Keegan’s The First World War (before I launch into the Second), my answer would have to be some kinda military radio system, preferably a bit dated so they can reverse engineer that bitch and then your comm problems are solved. Once the troops went over the top, the big problem for command was finding out how things were going, assessing it and deciding what orders to issue next. Having something other than runners, extremely unreliable radio or wired comms I think would be a major boon.
Perhaps a SR-71 blackbird? Problem is the fuel won’t be invented for decades.
A B-2 with attached 18 B83 nuclear bombs. A B-52 or a B-21 would probably work pretty well.
An A-10 warthog would put an end to trench warfare pretty quickly also.
Any one weapon won’t make a difference on Western Front, at least not one they can figure out how to use without a manual. So it has to be something they can reverse engineer and then build. T-34 and radio are pretty good bets, I was also thinking of AK-47 but I’m not sure how much difference it would make in trench warfare in the end.
They had already figured out to kind of materials to use, but they could never quite figure out exactly why it flew.
Compared to 1930 - 35, the same materials were being used, but the airfoils - wings, control surfaces, and esp. PROPS sucked.
Give them one workable fighter/bomber - 2 seater - they can figure out what they guy who ISN’T flying does - shoot, drop bombs. The differences in speed and maneuverability would be immediately obvious. As long as they have an ace who can handle the beast.
Would it be cheating to attach a machine gun using ammo already in existence? I don’t know it they had worked out ammo clips, but they had the Gatling Gun, so they knew how to feed ammo at least slowly.
And, to cheat a bit more - a few hundred-pounders with a variety of different fuses. Incendiaries would be nice, too.
What they lacked was not weapons, it was radios. The inability to exploit breakthroughs was what made large scale offensive operations fail over and over from 1915 to 1917. Portable radios could have solved that.
The odd thing is they might not have used it. Those officers were very attached to their horses and did not like tanks. Even up to WWII many were not convinced of the superiority of tanks until Patton proved their utility in the Louisiana Maneuvers.
A comprehensive strategy guide on the use of convoys and how submarines operate.
How about a manual on the construction and use of shell fuzes, the Allies had terrible problems with quality control of their shells, had the British had access to the same technology of shells and fuzes as used by the Germans, they would probably have sunk 6 or 8 German capital ships at Jutland
On land the difference is even more stark, with up to 1 in 3 allied shells not going bang, and Allied shells had a lack of explosive power compared to German ones, I believe that all it needed was the addition of some substance or other - aluminium sulphate?
