i need some complex engine management tips (spitfire and hurricane)

[klem]

Originally Posted by IvanK

The CLOD Merlin is overly critical in the climb with Oil and Rad Temps especially in the Spit MKII IMO.

This works for me:

Before start Prop pitch 3 blips back from full fine ... will give you 2850 in the climb.

1. After start Smooth idle Rad Closed till 60C Coolant. (no increase in throttle at all till 60C RAD ... thanks Klem))
2. At 60C Rad Full open.
3. Get airborne ASAP get to Climb IAS (160 ASAP)
4. Climb +9/2850 (Spit II) +6/2850 Spit MKI at 160MPH
5. Eyes on Oil Temp and Rad
6. Dont exceed 95C Oil, 120 Rad
7. If Oil temp at 95C Set RPM 2400 (or less) till Oil temp under control (94C is ok)
8. If Rad temp 120 set Boost +6(Spit MKII) +4 Spit MKI immediately (Aim for max 110C in the climb)

If >120C Rad you WILL get engine damage almost instantly.
if > 95C Oil Temp you most likely will get engine damage.
Oil temp main variable is RPM
Rad Temp main variable is Boost.
Dont exceed 2850RPM at any time.

Using these techniques in a spit MKII you can climb all the way to 17,000ft without issue. With perhaps a single
adjustment to RPM and Boost.

+1

Also interesting as we're talking Merlin III which is in the Hurricane MkI 100octane, my Level Speed tests showed that full throttle and full rpm, with and without BCO, will cause engine failure within the following:

30-60 seconds
OIL Temp 89-95
RAD temp 118-131

in various combinations

Combinations with temps below IvanK's limits were ~58 seconds 92 OIL and 118 RAD and another was ~60 seconds 89 OIL and 121 RAD so although I agree with IvanK's temperature limits there may be other issues modelled at fully fine pitch/max rpm (mechanical failure over time? ~60 Seconds if temp limits not reached?) so I suggest you don't use max rpm and max throttle for more than around 30 seconds. Sometimes you may want to just to stay with the 109s long enough to get the shot.

Another confusion is that I flew the Spitfire MkIa 100 octane for the first time (this patch) last night at around 15,000 feet with high throttle (boost 4 - 6) and 2550rpm in a long attack on a bomber group and the Oil temp was nailed to 100C without failure. (?!).

I have found 2550 rpm to be a 'safe' rpm under almost all conditions in the Hurricane. Last night was the first time in a SpitIa-oct so I can't be so confident on that but 100C Oil? Wow!