Changes to Siege Engine Rules at Pennsic War

Master Quinn Phelan, OL, DSEM for Siege, wishes to clarify rules for use of siege engines at the Pennsic War.

Master Quinn writes:

Greetings All,

Recently there was some confusion as to whether or not the Siege Rule Changes that were approved by Earl Robert, The Society Earl Marshal, would be in effect for Pennsic this year. He and I spoke about this issue and agreed that in the interest of safety it would be best if these changes were in effect. These changes were originally posted to many of you back in December of 2004 with a date for them to go into effect of April of this year. As a courtesy and to avoid people having to go back through and look things up, all changes that have been approved and are in effect are listed below. All of these changes are in reference to the July 2003 Siege Rules which are posted on the Society Marshal's Web Page. If anyone has any questions in regards to these rule changes, or needs clarification, or interpretation, please let me know as soon as possible, so everyone will have the same understanding of these rule changes come Pennsic.

Yours in Service,
Master Quinn Phelan, OL, DSEM for Siege

Changes to the 2003 Society Siege Rules;


  • Paragraph 2 line 2 delete the words  "simplification and"
  • Paragraph 4 delete entire paragraph

Siege Rules;
Add the following section;

  • Marshalling and Authorizations
    Each Kingdom shall report their activities involving siege to the Society Earl Marshall's Deputy for Siege on a quarterly basis. Any injuries resulting from siege activities that require professional medical attention will be reported to him immediately after the event where it occurred. It is recommended that each Kingdom Earl Marshal appoint a deputy to fulfill these duties and to oversee the Kingdoms Siege Program.

Each Kingdom will have a separate authorization procedure for any person wishing to operate or crew a siege engine. This authorization at a minimum shall include:

  1. Shall demonstrate a knowledge of the rules for melee combat
  2. Demonstration of understanding the rules for siege.
  3. Demonstration of being able to safely operate an engine.
  4. Demonstration of being able to inspect their engine for safety
  5. Demonstration of how to render their engine safe, should the need arise.
  6. Understand how engines/ engineers are killed by opponents.
  7. It is recommended that engineers be observed for at least 1 battle before their authorization is made final.

Marshalls trained in siege activities will oversee the inspections of engines and operators, and will be present on any field where siege engines are in use. During combat there will be a minimum of 1 Siege Marshal for each end of the field that has a siege engine. It is recommended that there be 1 Siege Marshal for every 3 engines in use.

Siege Marshals shall:

  1. be members of the Society for Creative Anachronisms
  2. be authorized in Siege Combat, or have gone through an appropriate training program
  3. have a basic understanding of all major engine types (Ballista / Arbalast, Catapult / Onager, Trebuchet- both counter weight and manpowered) to include being able to identify hazards, potential failure points, and soundness of construction.
  4. know how to inspect engines and ammunition
  5. know the current siege engine regulations.

In addition to these requirements, Siege Marshals that will be on the field shall:

  1. have at least 1 year of experience on the field as a Siege Engineer, or have gone through an appropriate training program
  2. Know the basics of Marshaling ( Refer to Marshals Handbook) and can do so safely. (Being a warranted heavy weapons marshal is recommended but not required)

SCA Siege Engine Criteria

  • Third paragraph first sentence, delete the words " Unless specifically exempted"
  • Third Paragraph third sentence, delete entire sentence.

General Siege Engine Regulations

  • Item 1 add the word "Siege" between "warranted" and "Marshal" (would read warranted siege marshal, instead of warranted marshal)
  • Item 3 first sentence, change from "...within the range of moving..." to "...within 5 feet of the travel path of moving..."  Delete second sentence of this item.
  • Item 7 delete the words " (such as gunpowder) "
  • Add Item 9 Engines (while they should not be struck with hand weapons) shall be built sufficiently strong enough to survive the rigors of combat, and could withstand either being struck with a full force blow, or being run into by a combatant.
  • Add Item 10 All engines must be free standing and may not use an operator as part of their support structure. Operators will not be included in measuring the footprint of an engine.
  • Add Item 11 All engines and ammunition will be labeled with name of owner, group, and Kingdom, for purposes of identification

Siege Ammunition Standards

  • Item 1 Change to read " No siege engine ammunition may exceed 1 pound in weight.
  • Item 2 Change to read " Siege Class Munitions must be colored with yellow tape in the following manners to denote them as Siege Class Munitions. Ballista Bolts must have their shafts and striking surface covered completely with yellow tape, and Rocks (both the 4 tennis ball and the 1 pound foam) must have at least 50% of their surface covered with yellow tape. These munitions may not be fired from small arms or thrown by hand. (this change was previously approved by the BoD but had not been changed in the rules as of this date).

Ammunition shall be constructed of the following materials:

  • Item 3 Tennis balls - may be punctured to relieve internal pressure with a hole not to exceed 1/16th of an inch in diameter. Tennis balls when used as the striking surface of a ballista bolt must be compressible by hand  with no less than 1/2" of compression and no more than 1" of compression.
  • Item 4 delete "or similar semi-rigid, shatter resistant tubing such as siloflex (PVC is NOT included in this definition)
  • Change Item 5 cord to Item 6
  • Add new Item 5 Siloflex meeting the following standards; for pipe that is black in color it must be - manufactured to ASTM D2239 or D2737, made from PE3408, be sized 1"ID if D2239, or 1-1/4" OD if D2737, have a SIDR rating of 15 or lower or have a SODR rating of 17 or lower. For pipe that is Yellow in color, it must be _ Manufactured to ASTM D2513, made from PE2406, be 1"IPS and have a SDR of 11.
  • Change Item 6 to Item 9
  • Change Item 7 to Item 10
  • Add new Item 7. Leather
  • Item 8. Lightweight fabric
  • Item 11 PVC reinforcement rings - may not exceed 2" in length.(Missile shafts may not be made from PVC)

Siege Ammunition Damage
At the end of the first paragraph add "Siege munitions are considered spent upon striking a target, the ground, or a battlefield structure. Siege Class Munitions that hit a tree will not be considered spent until they hit the ground or another battlefield structure"

Siege Ammunition Specifications

  • Item 2 section b sentence 4 delete the words "a 35-mm film container lid, "
  • Item 2 section c Add at the end "If Yellow Siloflex is used the shaft must not be covered with Yellow tape and the material specifications must be visible and legible."
  • Put the #3 before the paragraph on specialty siege ammunition

Crew Requirements
Delete this section

Add section Titled "Siege Engine Operation"

  1. Anyone operating a siege engine in combat will be armored to SCA minimum Heavy Weapons Armor requirements.
  2. Siege engine crews shall be made up of members who are authorized in siege, and are familiar with the engine that they are operating.
  3. Siege engine crews shall inspect their engines for wear, stress, and fatigue before each battle, and if possible, during holds.
  4. During holds siege engines crews may not cock, load, move, or in any other way make their engine ready.
  5. Siege engine crews shall immediately secure their engine should it become unsafe. They will remove the engine from the field at their earliest opportunity.
  6. Siege engine crews are responsible for the safe operation of their engine during combat. They are to make sure that crew members are clear of moving parts, and that non-crew personnel are not within 5 feet of the travel path of moving parts, and not directly in front of the engine, before discharging their weapon.
  7. Siege engine crews are responsible for the safety and condition of their ammunition, and shall visually inspect each round for damage before it is fired. (Ammunition that has been inspected prior to the battle does not need to be re-inspected before it is fired, but any ammunition that has been retrieved from the field does need to be re-inspected). Engines will not fire ammunition that is not designed for their weapon.
  8. It is recommended that siege engine crews give verbal commands for each phase of engine operation.

Add a section titled "Destroying Siege Engines and Siege Structures"
As siege engines can pose many risks to attacking fighters it is strongly recommended that great caution be exercised when approaching them. Be sure to stay clear of moving parts and try to approach them from the side. When engaging engines / structures, DO NOT STRIKE THEM WITH A HAND HELD WEAPON, while these items should be constructed to withstand such a blow, it is dangerous to do so as an accidental discharge of the weapon may result. Anyone found intentionally striking a siege engine / structure should be removed from the field, and possibly face further action such as a marshall's court. The proper way to Destroy these weapons is to safely approach the engine / structure, lay your weapon on it, and declare " this weapon is destroyed" (the same procedure as a declared kill from behind). This should be done in a safe and deliberate manner, and not in a rush while engaged with another opponent. Siege engine crews are all required to be in SCA minimum armor, and should be treated as any other fighter on the field. If they have a secondary weapon they may use it ( if authorized for heavy weapons combat) if not they may be killed as an un-armed / helpless opponent, if they yield do not strike them. Fighting should never take place over or around an active ( cocked or loaded) siege engine. If this situation arises a hold should be called and the engine declared dead. Siege engines and structures may also be destroyed by siege class munitions fired from a siege engine.

(The preceding section should also be included in the fighters handbook under it's own heading)

Appendix A

  • Add Arbalast- a tension powered Ballista (giant crossbow)
  • Add Ballista Bolt- a spear like projectile shot from a ballista
  • Change the definition of "Footprint" to Ground area covered by an engine as viewed from directly above, measured as length time width for engines with a square base and length time 1/2 the width for engines with a triangular or diamond shaped footprint.
  • Delete "Javelin" and it's definition
  • Add Mangonel- a man powered Trebuchet
  • For Trebuchet delete the word "traction" and replace it with the word "man"