Speaking of Merlins...

[Wing Nut]

So just for trivia's sake, when was the absolute first time a Merlin was fired up?

[Felix/FFDS]

When Arthur pulled the sword out of the stone?

[RichieB16]

When Arthur pulled the sword out of the stone?

Interesting answer...althought probably correct.  

[denishc]

 When I was 16, in the back of my garage........Oh wait....you asked when was the first time a MERLIN was fired up?

[Hagar]

When Arthur pulled the sword out of the stone?

Very good.

When I was 16, in the back of my garage........

I don't wish to know that. Way too much information.

If we're talking aero engines I don't know when the very first Rolls-Royce Merlin was run. It first flew as the PV-12 (Private Venture 12 cylinder) on the front of a Hawker Hart biplane in 1935. http://encyclopedia.thefreedictionary.com/Rolls-Royce%20Merlin

Another piece of useless information.

The first prototype (Versuchs 1 or V1) was completed by May 1935, but the German engines were not yet ready. In order to get the designs into the air, the RLM acquired four Rolls-Royce Kestrel VI engines by trading Rolls-Royce a Heinkel He 70 Blitz to test their engines on. Messerschmitt received two of these engines, and started work on adapting V1 to mount it. This work was completed in August, and V1 took its completed its early flight tests in September 1935. It was then sent to the Luftwaffe Test Center at Rechlin to take part in the contest.

The V1 referred to here is the prototype Bf 109. Meanwhile, the He 70 was used by Rolls-Royce as a testbed for the Merlin. Although it was a 7-seat airliner the He 70 held several speed records & was already faster than current fighters. Does this remind you of anything?

[ChuckMajik]

I'd say the Mosquito may have borrowed some design features. Or perhaps the He 111.

[jimclarke]

That has alot of the features of an He111.

Jim

[Wing Nut]

I can't believe no one can give me a date on this...

[Hagar]

I'd say the Mosquito may have borrowed some design features. Or perhaps the He 111.

The He 111 was certainly developed from the He 70. I was thinking more of a certain Supermarine design. It's difficult to imagine that R.J Mitchell & his design team were unaware of the Merlin-engined He 70 at Derby. It's quite possible he had a flight in it when the Merlin was being demonstrated. I'm not saying the Spitfire was a direct copy (as Ernst Heinkel believed) but the performance of that elliptical wing shape must have made an impression. It also had a very similar retractable undercarriage which was unusual at the time.

The He 70 was already one of the fastest civil aircraft in the world with the original 628 hp BMW engine. I can't imagine how it performed with a 1,000 hp Merlin up front.

[Wing Nut]

It kind of looks like a Spitfire on steroids!  ;D

[Felix/FFDS]

I can't believe no one can give me a date on this...

April (possibly February), 1935 on a Hawker Hart ?

[Wing Nut]

I don't know, I'm asking...  :)

[ChuckMajik]

I couldn't find the exact date, but I did find some interesting info.

The Merlin was originally called the PV-12.
It recieved a name change when the Air Ministry agreed to finance it's development.
And it's first type test was passed in July of 1934.

[Felix/FFDS]

THe first reference I've seen to a "Merlin" (as opposed to calling it a type PV-12) flying is that indication of it being tested in a Hart.

The PV-12 was originally developed with an evaporative cooling system - useful probably for a racer, but when glycol became available, the PV-12 was converted to this new cooling system.  It's hazy but I think this is about the time it started being called "Merlin"

[Hagar]

when glycol became available, the PV-12 was converted to this new cooling system

I think this is ethylene-glycol. Main source of supply from the US. Very effective as a paintstripper & incompatible with rubber insulation on electrical wiring. Spillage from the coolant tank directly above the main electrical loom led to a lot of maintenance problems on the Fairey Battle.

This reference keeps cropping up on searches & I can't find an exact date for the first test run on any web resource.

Prototypes of the PV.12 were ready for test in October of 1933, funding up to this point having been provided by Rolls-Royce as private venture money (hence the PV prefix). The Government supplied subsequent development funding. Prototype development work on the Merlin B through to F led to a number of modifications, including changes to the cylinder head and cylinder block casting, as well as the cooling system. First flight of a Merlin took place in April (possibly Feb) 1935 aboard one of Rolls-Royce's flying test beds, a Hawker Hart. Both the Hawker Horsley and Fairey Battle were also used as flight test aircraft during the course of development.

Interestingly it doesn't mention the He 70 testbed.