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Windshield Resistance:
The following resistance should be applicable to a new or used windshield.
Between terminals 1 and 2: -0.720 to 0.974 ohms @ 75 Degrees F +/- 5 degrees.
Between terminals 4 and 5: -0.720 to 0.974 ohms @ 75 Degrees F +/- 5 degrees.
Between terminals 3 and 6: this reading will vary with teprature changes.
the following are three examples, you will have to calculate anything in between.
Between 110 degrees F = 342 ohms
85 degrees F = 328 ohms
50 degrees F = 310 ohms

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Window shade P/N is as follows; all 1124 except 270-284 use CMA521240-119. For serial number 270-284 use CMA53139-101. For serial number 317 and subsequent serial numbered 1124s, the P/N is CMA53148-103. For 1124A, the P/N is CMA53148-101.

ATA 56

Windows, Direct Vision:

It has been brought to our attention that some of the DV windows installed in the Westwind fleet are showing signs of cracking / splitting / delaminating on the laminar plane. Part numbers affected are 343017-409, 343017-452 and 343017-97. Please inspect the window for cracking / splitting / delamination along the edge. The seal may have to be removed to see it clearly. Although the DV window is not specifically mentioned in the current revision of the AMM, IAI has determined that if there is this sort of deficiency in the window, it must be replaced. Please see the attached pictures of a window with delamination (dye penetrant was used to clearly show the separation)

ATA 56

Next time you are looking at your outer windshields, pay close attention to the little fiberglass pad bonded to the front lower surface of the glass. It is the static bonding strap for the windshield surface; and if it is eroded and missing, static can build up on the surface. When a windshield is replaced, cover the pad up with the same sealant used during windshield installation to protect it.

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Checking the Windshield Rain Seal
Reports of moisture between the inner and outer windshields of a Westwind 1124/1124A are common among owners/operators. Generally, this is caused by water getting past the outer windshield rain seal. Check the condition of the rain seal. Cracked or missing sealer could let water in, leading to this condition.

Desiccant that turns white quickly (indicating that it has absorbed moisture) or other visible signs such as water spots could also indicate the seal is bad. While your aircraft is in for maintenance, have the windshields purged with low-pressure nitrogen. Follow the Maintenance Manual procedures very closely if you do this yourself. Too much pressure will damage the windshield. As the system is purged, it can be quickly checked for external leaks.

If not repaired, an accumulation of water can cause corrosion to form on the windshield heat probes and surrounding structure, as well as causing improper windshield heat operation. Simply removing the old rain seal and applying fresh sealer will often keep the water out. Removing the outer windshield, cleaning and reinstalling it would be a last resort. The windshield desiccants should last between inspections, but always keep them fresh.