The SDBM (full name unknown), codenamed hypersthene (ハイパーシン), was an experimental weapon developed by Gründer Industries for use on the ADA-01A ADLER. Its destructive power was comparable to a nuclear weapon, without the radiation.
The ADA-01A ADLER was planned to appear in Ace Combat 5: The Unsung War, but was cut in development due to time constraints. Isshin Yabuki, who designed the aircraft, said in 2004 that it would carry the same burst missiles as those on the Scinfaxi and Hrimfaxi. Whether these burst missiles were supposed to be SDBMs is unclear; the SDBM wasn't introduced until Aces At War: A History was released in 2011.
The SDBM was designed as a successor to the Multi-Purpose Burst Missile, which was used on the ADFX-01 and ADFX-02 Morgan aircraft. It would have contained a very sensitive and destructive polynitrogen compound, allowing for massive damage over an extremely wide area; the weapon was described as having the power equivalent of a small nuclear weapon, without the risk of radiation.
The ADLER was planned to carry two SDBMs, one beneath each wing. However, due to the sensitivity of the polynitrogen compound, SDBMs needed to be stored at extremely low temperatures. To that end, the ADLER would carry two freezer-like containers with triple electromagnetic-radiation-protected walls synchronized in wavelength with the compound to safely carry the SDBMs. Once launched, the protective walls would open and electromagnetic energy would be used to propel the SDBM to glide towards its target.
Despite the ADLER successfully completing test flights, the complexity of the SDBM and its special housing containers indefinitely delayed further development on the ADLER, preventing its use in actual battle.
- The concept of a weapon with destructive power similar to a nuclear weapon without radiation was reused for Trinity in Ace Combat: Assault Horizon. Trinity was then used as the basis for the Multi-Purpose Burst Missile's appearance in Ace Combat Infinity.
- The SDBM's codename, "hypersthene", is a combination of two Greek words: hyper, meaning "very"; and sthenos, meaning "strong".