Three flights today: the first in an RE8 around the aerodrome – with an intriguing entry (‘Vacuum Control’) in the Remarks column – and two further afield flying in formation and on a compass course.
Log book entry
Date: 25.4.18 Hour: 2.50 Instructor: – Machine type and No.: RE 6647 Passenger: – Time: 45 m Height: 4500 Course: Aerodrome Remarks: Vacuum control
Date: 25.4.18 Hour: 5.55 Instructor: – Machine type and No.: DH6 7670 Passenger: – Time: 55 m Height: 2000 Course: Marlboro. Swindon. Aerod. Remarks: Formation
Date: 25.4.18
Hour: 1.10
Instructor: Lt Gowler
Machine type and No.: RE 3551
Passenger: –
Time: 50 m
Height: 2000
Course: Compass course (Wootton Basset, Chippenham &
Devizes. 5 forced landings)
Remarks: DUAL
Vacuum Control
So what was the ‘vacuum control’ of the first entry (but not the first flight) of the day? I’m grateful to Duncan Curtis, who has provided this authoritative explanation:
‘Vacuum Control’ relates to a feature on some aircraft/engines, whereby the carburettor/s were equipped with vacuum controls. The vacuum control feature allows the pilot to adjust engine mixture for altitude: on early engines no adjustment; then on some engines manual adjustment; and finally all engines gained automatic adjustment via vacuum bellows (post-WW1). For service types equipped with these engines (of which the RE8 was one), the pilot had to demonstrate correct operation prior to graduating ‘B’ on his operational type.
[Topic updated 25 September 2018]
Formation Flying
The second aerial event of the day was some formation flying on a circuit from Yatesbury to Marlborough to Swindon and back, a distance of some 30 miles (48 km):
Cross Country
The third entry in the log book, but actually the first flight of the day, was a cross-country compass course under dual control with Lt Gowler as instructor. The course was a 34 miles (54 km) circuit from Yatesbury to Wootton Basset to Chippenham to Devizes and back.
