.

Scheme Colour name FS number BS number Humbrol XtraColor Vallejo ModelColor Vallejo ModelAir Hataka
Standard #1 Overall Dark Blue ~5042   181 X121 70.898   -
 
Standard #2 Upper sides Extra Dark Sea Grey ~6099 BS:640 123 / 106 X-5 / X-376 70.866 71.110 ~140
Underside Sky - BS:210 90 X004 / X130 - 71.302 ~026

Check www.paint4models.com for an extensive conversion table with lots of colour and paint systems.

Sikorsky HO4S-3 1-SMALL
The delivery scheme of the Sikorsky HO4S-3: Overall dark sea blue, with white markings.
Initially there was no name applied on the nose of the aircraft.
Further, the "bulges" (doppler radar ?/) under the hull hadn't been applied yet and also the early light hoist was applied above the sliding door.
Who knows more about these bulges??
Sikorsky HO4S-3 2-SMALL
The second scheme of the Sikorsky HO4S-3: Sky with dark grey upper sides and black serials.
Also the name was applied in black. Note the positioning of the name might differ. Still with the early hoist.
Sikorsky HO4S-3 3-SMALL
The first paint scheme but the new serials and name in white. Still the early hoist was applied.
Sikorsky HO4S-3 4-SMALL
The last paint scheme of the Sikorsky HO4S-3: sky with dark grey upper surfaces; black serials an name.
Note the new hoist, capable of hoist larger loads.