Toothless Stator Laminations Nonmetallic Winding Support Simple Rotor Construction Tooth-Type Stator Four-Pole Rotor Large Magnetic Air Gap (a) Toothless Stator Two-Pole Rotor (b) Figure 4. The (a) multiple-pole and (b) two-pole PMM designs. next-generation launch technology (NGLT) program. This is a joint effort of Lockheed Martin Aeronautics and Honeywell Aerospace-Torrance. The turbine power unit combines foil bearings, a turbine shaft seal, an HRPMM, and a reaction chamber with a turbine wheel and housing. The unit is shown in Figure 6. The turbine power unit wheel is a single-stage, axialimpulse design. It is made from powered-metal Astroloy, which has particularly good hydrogen embrittlement resistance at high temperatures. The turbine housing is a hog-out machined from Inconel 625. It includes an integral turbine containment ring. The unit is liquid-cooled. The housing includes an integral water jacket. The HRPMM stator is pressed inside this cooling jacket. The EM rotor uses twopole, samarium-cobalt magnets encapsulated in an Inconel sleeve. A three-dimensional rendering of a unit cutaway is shown in Figure 7. Figure 5. The PTMS for the JSF incorporating an HRPMM. (Photo courtesy of Honeywell International.) Figure 6. An example of a turbine power unit. (Photo courtesy of Honeywell International.) Figure 7. A cutaway view of the turbine power unit in Figure 6. (Image courtesy of Honeywell International.) IEEE Electrific ation Magazine / d ec em be r 2 0 1 4 21