OP 1664 U.S: Explosive Ordnance (Vol. 1); Chapter 8 - Aircraft Pyrotechnics; Section 1 - Pistol and Hand-Size Signals: Double-Star AN-M28 to AN-M33 Series (Obsolete)

U.S. EXPLOSIVE ORDNANCE

PART 3 - PYROTECHNICS

Chapter 8 - AIRCRAFT PYROTECHNICS

Section 1 - PISTOL AND HAND-SIZE SIGNALS

Double-Star AN-M28 to AN-M33 Series (Obsolete)

Length, inches	3.02
Diameter, inches	1.58
Burning time, seconds	7
Altitude, feet	250

Use: Double-star aircraft signals are used as emergency identification by aircraft.

Projection: The Pyrotechnic Pistol AN-M8 or Projector M9 is used for firing the signal.

Description: The signal cartridge has an aluminum, plastic, or steel barrel with an ex-traction groove at the closed end which houses the primer. A press-fitt identification top is cemented into the opposite end, finished with embossed letters to identify the colors of the stars. Approproately colored bands around the outer case also identify the colors of the stars. In addition, the identification top is appropriately colored. These signals are also classified by the Army as the "Rimless Type".

Color of Stars		Embossed Letters
AN-M28	Red-Red	RR
AN-M29	Yellow-Yellow	YY
AN-M30	Green-Green	GG
AN-M31	Red-Yellow	RY
AN-M32	Red-Green	RG
AN-M33	Green-Yellow	GY

Operation: The firing pin of the pistol strikes the primer, igniting the propelling char-ge. As the stars are expelld from the pistol, they are ignited by the propelling charge through the quickmatch. The stars reach full brilliance after travelling 40 or 50 feet, and rise to a height of approximately 250 feet.

Figure 170. Cartridge Signals M11 and AN-M28 to 33 Series

Figure 171. Cross Section of Cartridge Signal AN-M31