Sans,
It's pricey, no question. The exact delta versus the Osprey depends on the specific cost figure used, however.
The
GAO figure of $131M/aircraft is a fully burdened 'program unit cost' number, which includes R&D. Looking at the latest
SAR data available (from December 2016), the CH-53K's program unit cost has risen to
$156M/aircraft
($31 Bn program cost, spread across 200 aircraft), while the V-22's equivalent cost is
$122M/aircraft
($56 Bn program cost, spread across 462 aircraft). So by this metric the King Stallion is 28% more expensive.
The actual unit flyaway costs (i.e. excluding R&D and GSE/training, etc.) are - of course - lower. Using the most recent SAR reports issued for both programs (March 2016), the
CH-53K's recurring flyaway unit cost is
$94M, while the
V-22's recurring flyaway unit cost is
$76M (this figure being a composite of the vanilla MV-22 and SOF's pricier CV-22). So by this metric the King Stallion is 24% more expensive.
(For comparison, the
CH-47F's March 2016 SAR shows a program unit cost of
$27M and a recurring flyaway unit cost of
$25M, the R&D associated with the F program having of course been far lower than that related to the clean-sheet Osprey or the
only-the-dataplate-stays-the-same CH-53K.)
I/C