Axis and Allies Revised: A Beginner’s Guide to Tech:
The utility of tech varies wildly depending on whether out-of-the-box rules are used, the FAQ available on the Wizards website, or Larry Harris Tournament rules (1.3 is the current version as of this writing). Particular National Advantages also change the utility of tech.
1. Rockets. This is the most unbalanced tech in Out of the Box rules. All a player needs to do is get the Rocket tech, and after that, all of that player’s AA guns will be able to effectively take away one dice of IPCs from an opposing player within range. Germany in particular can use this tech effectively, producing mass AA guns and shutting down both Russia and UK’s production while playing defensively; in a few rounds, Germany can turn the tables and start attacking. This tech is frankly pretty ridiculous in the Out of the Box version.
To be more specific, the Germany player can, say, invest 20 IPC in Rocket tech, having a 51.8% probability of succeeding. If succeeding, Germany can buy 4 AA guns. On Germany’s first turn, if the tech research succeeded, Germany can immediately take 3 dice worth of IPCs from the United Kingdom. On the second turn, if the tech research succeeded on the first turn, Germany can take 7 dice worth of IPCs from the United Kingdom and buy more AA guns. If the tech research failed on the first turn, Germany can roll for tech again and buy more AA guns. By the third turn, depending on the tech research results, Germany may be doing as much as 15 dice of economic damage to the United Kingdom and/or Russia. In practical terms, Germany can’t really do that much economic damage to Russia until Germany moves its AA guns into range of Russia, but it is clear that Germany can quickly neutralize both countries’ income. There is really nothing that either UK or Russia can do about it either; Germany can attack UK with AA guns in Germany, and Russia with AA guns in Eastern Europe, and both territories are extremely difficult for the Allies to capture.
The rules for Rockets changed in FAQ and LHTR. There, any particular industrial complex can only be attacked by one AA gun per turn. Germany can still use Rockets effectively, but due to the firing limitations, the tech is no longer as exploitable as it once was.
2. Long Range Aircraft. This is a good tech for two reasons. In OOB (out of the box) and FAQ rules, Long Range Aircraft can be used to immediately add range to fighters, adding a possibly unanticipated amount of force to an attack; this can make otherwise unfeasible attacks can become feasible. In LHTR, tech advances don’t take effect until the end of the turn, but Long Range Aircraft can still be useful; if Germany gets it, Germany can use the extra range to use fighters landed in Western Europe to threaten most of the Atlantic, while still having the range to hit Russian territories and land back in Western Europe. If Japan gets it, Japan can use its fighters to attack Asia while defending the Pacific against US naval attack. If the US gets it, the US can use its fighters to extend its effective range against Japan, taking island bases and building mass fighters to destroy the Japanese navy.
Particular OOB/FAQ uses of Long Range Aircraft include the first-turn German invasion of London (called G1 Sea Lion, for “Germany 1 Sea Lion”), unexpected US air attack on Japanese transports in the Pacific, and unexpected Japanese attack on Western U.S. or isolated US transports (the former usually after taking Hawaii or Western Canada from Japan; on the next turn, Japan adds 6 fighters and a bomber that the US player didn’t count on).
G1 Sea Lion is not a clear win for the Axis. First, Germany has to get the tech; if Germany invests a lot of IPCs in the tech but fails to get it, that’s a significant handicap and a probable loss. Second, Germany will probably lose a lot of air on the attack; if lots of air is lost to an AA gun, it can be disastrous, losing Germany the attack on London as well as the immediately losing air. Even if the UK AA gun doesn’t hit anything, German air will very likely be depleted against UK’s defenders. Third, even if Germany does take London, it will probably only be with very minimal forces, allowing UK to retake with a battleship support shot and tank from Eastern Canada (collecting income at the end of its turn), after which the U.S. can move in reinforcements on the first US turn. At that point, Germany will have a lot of IPCs, but almost no air; the Allies will be able to set up an Atlantic transport fleet with little fear of the weakened German air, and UK has IPCs to defend London.
For that reason, if Germany does decide to go for a G1 Sea Lion, it is very highly recommended either that Germany should start the game with an extra Baltic transport (allowing better odds for the London attack, and allowing more German air units to survive the attack against the London defenders), and/or Germany should buy transports as well as the requisite Long Range Aircraft tech dice on the first turn (if Germany has three transports available for the start of G2, Germany can probably recapture London from the UK/US forces).
3. Heavy Bombers. This is generally not a good tech. That is particularly true for LHTR, which weakens the effect of Heavy Bombers and strategic bombing. Under OOB or FAQ rules, though, a US player can use this well in conjunction with the Heavy Bombers National Advantage. (LHTR rules change the effect of the Heavy Bombers National Advantage).
That is, the US player can build two bombers on US1 and fly its existing bomber to London; on US2, the US player can build three bombers and fly the two bombers built last turn to London, and bomb Germany for 1 dice; on US3, the US player can invest in Heavy Bomber tech, fly the three bombers built last turn to London, and probably bomb Germany for 6 dice (3 dice if the eight or so dice the US can sink on tech all fail); on US4, the US player can go for Heavy Bomber tech if it failed the first round (getting another eight dice for tech), and almost certainly hit Germany for 12 dice worth of IPC damage. After that, Germany is pretty much out of the game, and the Allies can go on and do whatever they want.
4. Jet Power. This is not a particularly good tech using FAQ/OOB rules, but it is slightly better under LHTR, as LHTR adds the ability to avoid AA fire.
Instead of sinking IPCs into tech to get a more efficient fighter defense, it is typically better to just buy more fighters, getting another unit that can be taken as a casualty, as well as more attacking power. LHTR adds the ability to avoid AA fire, which means that fighters can be used far more reliably in exchanging territory that may have AA guns moved in. Although the LHTR change to the tech is a very nice bonus, this tech is generally not worth pursuing (although there may be exceptions, for example if a player has lots of fighters, and an opponent has lots of AA guns)
5. Combined Bombardment. This tech is, I think, not useful until the very end of the game, at which point the game should already be effectively decided. This is for three reasons; first, no power starts with a lot of destroyers (so no power is ready to exploit this tech), and second, destroyers are of very limited use, and expensive, so attempting to buy destroyers and research tech at the same time allows an opponent to gain territory, which means that even less IPCs will be coming in to buy destroyers and research tech, and third, no power is poised to immediately take advantage of a tech research (particularly so with LHTR)
I think it may be feasible to attempt to exploit the Combined Bombardment tech with the UK or US under certain circumstances, or possibly with other powers under really unusual circumstances. However, I think it extremely risky at best.
Destroyers are rarely cost effective. A carrier and two fighters offer a superior defense at the same price as three destroyers, but has the ability to hit ground targets as well (with the fighters); three subs offers similar attack and defense power, but added durability, when compared to two destroyers (the subs can afford to take more casualties). Destroyers can hit enemy air, and have an antisub effect, so destroyers can be useful. However, any particular fleet will usually find it most effective to take along only one destroyer, and build either mass subs, mass carriers, or preferably a combination of the two. Even Japan with the “Tokyo Express” national advantage, will probably not want a lot of destroyers.
Near the end of the game, when one of the powers is sitting on a stack of infantry on its capital, that stack of enemy infantry can be reduced by Combined Bombardment tech. To do so, a power needs to have lots of destroyers, and enough IPC to successfully research Combined Bombardment; once the research is successful, a single infantry can be amphibiously landed, and however many destroyers are present can use their support shot. By doing so, a power can spend 3 IPC (the cost of one infantry) and destroy up to 10 or more units. Of course, to destroy 10 or more units, about 20 destroyers would have to be present, which is massively expensive (20 destroyers cost as much as 48 tanks).
However, the destroyers have two advantages. The first advantage is, naval units can be produced anywhere. Over time, the US can easily put 20 destroyers in the water and sail towards Japan or Germany. Getting 48 US tanks into Europe is a different matter, with a limited number of transports and no US industrial complexes in Europe. The second advantage is that destroyers protect the water; an enemy power that has an infantry stack on its capital may also be massing air to destroy any navy around it (in doing so, destroying the transports that are ferrying units in to contain the enemy power).
6. Super Subs. Pretty self-explanatory, they’re super subs. If you are going to use a lot of subs, this can be worth researching. If you’re just going to use a few subs, this is not a great tech to go for.
In a regular game, if one player invests heavily in navy, a player may counter with a gigantic sub fleet and Super Sub tech research. Of course, if Germany or Japan invest heavily in subs, pressure on Russia is lessened, if UK invests heavily in subs, ground unit reinforcements to Europe and/or Africa is lessened, if US invests heavily in subs, ground unit support to Africa, Europe, and/or the Pacific is lessened (although the Pacific ground pressure is probably not a problem, as naval dominance over Japan must be established first).
If playing with LHTR and National Advantages, though, Super Subs can become far more formidable combined with the Kamikaze or Kaiten NAs. With that NA, Japan can target enemy destroyers, allowing their subs to always get the first strike advantage. If the US opted to go transports, carriers, a destroyer and battleship, a Japanese super sub attack can be very strong. However, the US can potentially counter with its own sub fleet (since defending subs will get to fire during the opening fire step, essentially eliminating Japan’s first strike advantage), so even Kamikaze/Kaiten and Super Subs does not guarantee dominance of the Pacific for Japan.