Mosquito NF.Mk XIX low altitude performance with N2O boost

[Neil Stirling1]

Earlier, I posted that this document had been doctored, however I have been in contact with the originator ( who I hold in high regard) of the modified document. I can catorgorically state that it was his intention to provide 2 important pieces of information on one scan.


Neil.

[Neil Stirling1]

HoHun, the speed figures for this aircraft are at +25lbs boost and with wing tanks, the exhausts were the flame damping saxophone type, reckoned to reduce speed by 13mph to 15mph.  the date December 43 to Jan 44.

12th part of report No A.& A.E.E/767,e

Contained within AVIA 15/1681.

I will probably post some of this over at Butch's site.

Neil.

[AGJV44_Rot 1]

Adolph Glunz was usually called upon singally to go hunting Mossies that were flying near there base when he was in JG26.  He was the mossie killer.

[HoHun]

Hi Neil,

>12th part of report No A.& A.E.E/767,e

>Contained within AVIA 15/1681.

>I will probably post some of this over at Butch's site.

I'm looking forward to it! Could you cross-post it here, too? Thanks in advance!

Regards,

Henning (HoHun)

[Neil Stirling1]

HoHun I prefere to post over at Butch's site, however if you have problems accessing the other site post your E-mail address and I will see what I can do.

Neil.

[HoHun]

Hi Nail

>HoHun I prefere to post over at Butch's site, however if you have problems accessing the other site post your E-mail address and I will see what I can do.

Not a problem, just go ahead!

Regards,

Henning (HoHun)

[HoHun]

Hi Neil,

Thanks, I got the information now!

As the Merlin 25 couldn't get the full +25 lbs of boost at sea level but just +23.9 lbs, that's the lack of ram air pressure responsible for the engine not providing full power at sea level. (The full throttle height for MS gear is negative :-) I'd say instead of the 2000 HP mentioned in some sources, the Merlin 25 only gave 1900 HP.

The speed curve for the HX809 doesn't match the one posted as "HX802" curve, which is fine as it matches the Merlin 25 power chart better with FS full throttle height being a bit lower than the 8000 ft indicated by the engine chart, for the same lack of ram effect. (It might be "HX802" is a bogus chart resulting from sloppy processing of HX809 data. That shook my confidence in the nice curves from that Mossie book.)

I've used the HX809 data in an attempt to get some estimates for the deck speed of a Mosquito with ejector exhausts and no drop tanks. The problem I have now is that HX809 doesn't match the speed chart for the FB 6 at +18 lbs/3000 rpm, being too slow around and above FS gear full throttle height.

I can't locate the problem exactly yet as I've used the FB 6 data as basis for determining the effects of drop tanks and ejector exhausts (assuming the TR 33 differs only by the exhaust configuration). If I assume a different configuration as the basis for that FB 6, my estimates for a "clean" HX809 go down the drain :-)

Regards,

Henning (HoHun)