Hawker 800XP 23491-3 vs RG-390E Main Battery

Two records and two evidence tracks

The 23491-3 record and RG-390E record both appear in the IPC. The replacement statement comes from a separate manufacturer document.

Question	IPC evidence	Concorde eligibility evidence
Is the number present in ATA 24?	Yes, both numbers appear	Not the purpose of this source
How many are printed?	Quantity 2 at ZM and ZN	The STC description also specifies two RG-390E batteries
Does the IPC print a replacement?	No	STC ST00415LA is identified as the replacement path
What batteries are replaced?	Not stated as a relationship	23491 or 23491-3 nickel-cadmium batteries
Which models are named?	Combined IPC publication scope and serial effectivity	Hawker 800 and 800XP among the listed models

Keeping those columns separate prevents the STC statement from being misquoted as IPC language.

23491-3 IPC record

The IPC calls 23491-3 the ZM and ZN battery and prints quantity 2. It appears in five rows across Figures 24-30-05-20, 24-30-05-20C, and 24-50-05-21.

Some rows carry SB24-266. The serial ranges are fragmented and differ by figure. The part record retains every reviewed block so a researcher can match the aircraft to the applicable row.

The IPC does not print RG-390E as a replacement on those rows.

RG-390E IPC record

The IPC also calls RG-390E the ZM and ZN battery and prints quantity 2. It appears in Figure 24-30-05-20C, item 50 and Figure 24-50-05-21, item 375.

The two rows have different effectivity lists. They are both useful, but neither is a substitute for reading the aircraft serial and configuration against current approved data.

RG-390E STC path

Concorde’s aircraft eligibility material identifies STC ST00415LA for Hawker 800 and 800XP aircraft. The document states that two RG-390E batteries replace either Hawker Energy 25 Ah batteries or SAFT 23491 and 23491-3 nickel-cadmium batteries under that installation path.

That is not a loose catalog cross-reference. It is an installation basis with approved data that has to be followed.

Do not treat an RG-390E purchase by itself as completion of the conversion. The aircraft records, installed configuration, STC status, required hardware, and instructions must agree.

Chemistry and shop handling

23491-3 and RG-390E are not just two labels for the same battery chemistry. The replacement path moves from a nickel-cadmium record to Concorde’s sealed lead-acid battery installation.

That distinction affects the maintenance and configuration review. This page does not provide charging, capacity-check, venting, temperature-monitoring, or installation procedures.

Keep the emergency battery separate

100-0540-04 is an XL245-C emergency-battery record. It is not one of the ZM and ZN main-battery records discussed above.

Do not merge main-battery and emergency-battery quantities when reading ATA 24. They serve different catalog roles and appear in different installation items.

Sourcing checklist

For 23491-3, send the exact battery number, aircraft serial, installed position, current chemistry, service-bulletin status, and maintenance records.

For RG-390E, also state whether STC ST00415LA is already embodied or is the intended installation path. Ask for condition, manufacturing date, traceability, release paperwork, and any shelf-life or shipping limits that apply to the offered battery.