Spit IIa is now so much more inferior to the 109

[CaptainDoggles]

Spit is only worse if you are one of the noobs flying around on the deck, turning circles kicking up dust.

My wingman and I confronted some Spitfires up high over England two nights ago and they were extremely formidable.

Can we please put this tired topic to rest?

[Bokononist]

Originally Posted by CaptainDoggles

Spit is only worse if you are one of the noobs flying around on the deck, turning circles kicking up dust.

My wingman and I confronted some Spitfires up high over England two nights ago and they were extremely formidable.

Can we please put this tired topic to rest?

Good pilots are good pilots for sure Doggles, and I class myself as a distinctly avarage pilot at best! The issue though is caused by the fact that this a simulator designed to model the battle of Britain which was fought with Hurricanes and Spitfires (both 1 and 2s) all modified for 100 octane fuel. What we have are planes that are not the ones that fought this battle. Whatever the standard of pilot is not really relevant here, the reds are flying the wrong planes for the BoB. Of course people are annoyed, and with the game in a state of flux at the moment those people want to bring the subject to the attention of as many people as possible, in the vain hope that the devs will acknowledge and correct this glaring historical error.
Boko.

[camber]

Originally Posted by Crumpp

It seems very likely that RAF pilots were authorized to "pull the tit" on their aircraft using 87 Octane fuel with a lower manifold pressure boost gain. It appears to be independant of 100 Octane fuel use.

Dear Crumpp,

I think this is incorrect about the Spitfire boost control cutout. It actually had quite different roles pre and post modification.

The original boost cutout was a true "cutout" in case of failure of the boost controller (which controls at +61/4psi). It gives full throttle valve control back to the pilot, enabling him to get +20psi boost (full unthrottled supercharger output) at ground level if he desired. Of course with either 87 or 100 octane this would not be a good idea.

There is no documented use of the original boost cutout as a combat boost system I am aware of, but it would be possible. The pilot would need to be very careful not to exceed a boost level that caused predetonation or engine damage, and the boost would continuously change with rpm, height and throttle position.

That document giving 10.55 psi boost is very interesting. As Banks suggested, it appears to be the boost attained with full throttle and (unmodified) boost cutout pulled at height. The height is about right. Interesting in that such a high boost was usable at all in a Merlin III on 87 octane.

However it is very unlikely that pilots were ever authorised to use the unmodified boost cutout as emergency power because the risk of instant degradation of engine performance was high (especially at low altitudes)

When the boost cutout was modified it was actually no longer a "cutout". It became a boost setpoint changer from +6 1/4 to +12 psi. It then became authorised as a practical combat boost (in conjunction with 100 octane fuel) that Dowding could fret over.

camber

[41Sqn_Banks]

Originally Posted by camber

There is no documented use of the original boost cutout as a combat boost system I am aware of, but it would be possible. The pilot would need to be very careful not to exceed a boost level that caused predetonation or engine damage, and the boost would continuously change with rpm, height and throttle position.

Guidelines for use of boost control cut-out in unmodified condition, January 1939:

[Crumpp]

There is no documented use of the original boost cutout as a combat boost system I am aware of, but it would be possible. The pilot would need to be very careful not to exceed a boost level that caused predetonation or engine damage, and the boost would continuously change with rpm, height and throttle position.

That document giving 10.55 psi boost is very interesting. As Banks suggested, it appears to be the boost attained with full throttle and (unmodified) boost cutout pulled at height. The height is about right. Interesting in that such a high boost was usable at all in a Merlin III on 87 octane.

However it is very unlikely that pilots were ever authorized to use the unmodified boost cutout as emergency power because the risk of instant degradation of engine performance was high (especially at low altitudes)

I agree that specific authorization was probably not given and the risk was high.

The RAF pilots were given license to use it in the General Operating Notes. The Air Ministry openend the door and I am sure pilots died as a result.

They were instructed to balance the risk. Given the fact these guys were not the technically savvy pilots we see today, it makes sense you would have a high incidence of those who thought they knew better with such instructions.

Defining that point of balance was obviously an issue for the RAF as several memo's appear at various times during the war warning of the dangers of over boosted conditions.

[41Sqn_Banks]

Originally Posted by camber

However it is very unlikely that pilots were ever authorised to use the unmodified boost cutout as emergency power because the risk of instant degradation of engine performance was high (especially at low altitudes)

Absolutely correct. In fact the were not authorized.

[Crumpp]

Absolutely correct. In fact the were not authorized.

So the argument that the airworthiness limitations were free to be violated because the RAF says to balance risk only works when it fits an agenda?

[41Sqn_Banks]

Originally Posted by Crumpp

So the argument that the airworthiness limitations were free to be violated because the RAF says to balance risk only works when it fits an agenda?

Where does RAF authorities allow to ignore/violate engine limitations? My agenda is to follow primary sources, this makes life pretty easy.

[Seadog]

Originally Posted by Crumpp

So the argument that the airworthiness limitations were free to be violated because the RAF says to balance risk only works when it fits an agenda?

We know your agenda.

The RAF's agenda was to provide the pilot with the best possible performance in high risk combat situations. The RAF didn't want to provide the pilot with an engine self destruct switch, which is what would happen if the boost override was used with 87 octane fuel.

[fruitbat]

Originally Posted by Seadog

We know your agenda.

The RAF's agenda was to provide the pilot with the best possible performance in high risk combat situations. The RAF didn't want to provide the pilot with an engine self destruct switch, which is what would happen if the boost override was used with 87 octane fuel.

+1

Its just Crumpp trying to ignore all the pilot accounts regarding using the boost ie pulling the plug etc,being linked to 100 octane fuel because it doesn't fit with the agenda he's pushing.