31 March 2018

Fantastic Fortress: Attacks from the Air

I've been doing research lately on historical anti-aircraft tactics. Looking at what has been published in places like Dragon magazine and then suggestions on the internet about how best to defend against aerial attacks don't satisfy me. Typical suggestions rely too much on magic especially spells specific to D&D, or monsters being tamable. There has to be a more mundane, simpler and cost effective method to defend against aerial attacks from flying monsters, like dragons, with ancient/medieval levels of technology. This article is going to be the first in a series of posts about how a castle would change to defend from the fantastic attacks inherent in a standard fantasy world.

Historically there seems to be 4 main methods to withstanding an aerial assault: defensive aircraft, advanced warning systems, anti-aircraft guns, and bomb shelters. I am going to detail possible fantasy analogues for each method of defense that relies on mundane techniques and not magical spells.

Concerning flights of fighter planes to defend air space, the most common thing that seems to pop up on the internet when air defenses are talked about are flights of knights on trained hippogriffs. Even in a high magic setting I find this solution extremely implausible. I consider hippogriffs to be more like zebras in temperament than a horse. If we're going to go with flying mounts the most likely creature would be a Pegasus or pegataur, but that still requires a setting with all the prerequisites for raising and feeding and training these mounts. They would be obedient to their rider and probably no one else. We would see only the elite with these types of mounts. Whatever the mount is it would have to be domesticated, easily stabled and fed and with an easy way to ride them and still use weapons of some sort. An alternative to a mount would be to befriend a flying beast who can ward off hostile monsters. This could be a lawful dragon or sphinx, or even a flying construct of some sort made specifically for this purpose.

Creating equivalents of advance warning systems may prove to be the most daunting task I have set for myself. Barring magical scrying techniques(and who can afford to pay those extortionist wizard fees anyway) there is no low tech version of radar. Therefore, it is necessary to look to solutions that were used in war before the advent of radar but after the invention of flight. One example used towards the end of WWI was an acoustic detection system. Relatively primitive methods were used at first with multiple metal cones used to identify the distance and direction of incoming aircraft. This was later developed into huge concrete sound mirrors and walls.
German Acoustic Locator 1915

British Sound Mirror 1928
British Sound Wall 1930  
The sound mirrors could detect aircraft 20 to 30 miles away, and with the proper electronic equipment a range of up to 50 miles was claimed. Even without electrical amplification the utility of these devices was impressive. Of course in a low tech environment concrete would probably not be used. It might be more economical to make the large mirrors/walls out of stone blocks or carve them into a mountainside. In either case such an endeavor would require vast resources only available to a large organized state and not a standard feudal kingdom. In the case of less centralized governments the small mobile or personal sound locators might be more common. Regardless the most intelligent use of these devices would be to have several near the outer boundaries of the territory with a line of signals, whether that be fires or reflective mirrors or pigeons, to alert major areas of population about incoming threats.

Concerning Anti-aircraft guns, this seems to be the easiest solution to solve. As a replacement for the guns themselves, ballistae could prove useful. The ballista could even be modified in a way to fire multiple missile in quick succession similar to the chinese chu-ko-nu.

Think this but big enough to kill a dragon
Other factors play into anti-aircraft than just the guns though. The use of mobile guns and emplaced guns working in conjunction was essential. Both of these are fairly simple to accomplish with ancient technology. Mobile guns can be placed on carts or boats or even simple rail systems(mule powered) connecting key areas of defense. During the latter part of WW2 the germans built several concrete fortresses to mount big anti-aircraft guns on. They were built in pairs, one had lighter defenses and was focused more on range finding while the central one caused the most actual damage to aircraft.

Looks kinda like a castle, huh?
Again these wouldn't be a grand change for medieval architects, simply adding emplacements for ballistae on top of a castle would probably suffice. Though in some cases height may be an issue, as the german towers were more than 100 ft tall and most historical castles didn't reach those heights as far as I know. Height/range may also prove an issue for ballistae too; the range of historical ballista was nothing like a standard flak gun. I guess it depends on how high the target is flying.

The last aspect of air defense seems to already be solved for us. Pretty much every castle and city in most fantasy worlds seems to have underground mazes and dungeons of one sort or another. A logical explanation for the purpose of such complexes is as bomb shelters. So, problem solved right? Probably not. I don't see a real need for bomb shelters in a fantasy world. Dungeons are still an inexplicable mystery for the most part. The problem is this; in a typical fantasy world there are no bombs! What is the point of a bomb shelter without bombs? Yeah, OK, an enemy could take a lot of big boulders and use flying mounts or spells to drop them from great heights(something pretty common in most games I have played), but these simply don't have the destructive power of actual exploding bombs. Without gunpowder or an equivalent to construct exploding shells the use of a bomb shelter is doubtful. Yes, being underground would protect against falling rocks, but so would a sturdy roof made of stone and angled in such a way at to deflect incoming missiles. This may prove as a point in favor of building underground to begin with. But this may cause other problems which we will get into next time.

The next post in this series will discuss threats from below for a Fantastic Fortress, and after that we may discuss the effects of D&D magic or land based monsters, and then finish with an example combining all elements and compare it to historical castle construction.