Come fly with KA 114

[Airspeed]

IIRC, when I was about 12, I watched a WW2 film about a downed British pilot who woke up in a German hospital.
They were trying to convince him that he was in England, hoping to make him chat about secret details.
He realised where he was when German aircraft flew over and there were no sirens or defensive fire.
I thought he mentioned the engines not being synchronised, and "learnt" this "fact", which I carried in my useful knowledge database until today.
54 years of wasting brain space on that one.

[Garry Russell]

That could be whether or not the engines were synchronised manually or not

[Archer]

To get two engines synchronised you have to get the prop levers into a position where the RPMs match. This is best done by ear, but in later types (think 50's and later) gadgets turned up which helped the pilot achieve this, leading to automatic prop sync systems on newer generations. Light twins that fly around these days still don't normally have any type of automatic syncing, so you have to try to get the RPMs to match on every power change which involves a RPM change. For a PA44 (Seminole) you take off with 2700 RPM, pull that back to 2500 RPM in the climb and then back to 2400 RPM for cruise, the prop levers are then pushed to high RPM again on final.

[DaveB]

No sirens or defensive fire when he was lying in a German hospital when German aircraft flew over may well have meant that the Germans were aware that the aircraft coming in were their own

That routine for the Seminole must be pretty much the same for any multi engined aircraft without prop sync. It's the way I fly all of ours on the VA anyway Nice to see the RW is getting it right

ATB
DaveB

[cstorey]

Absolutely brilliant film . Noteworthy how he kept the nose well down so as to achieve safety speed a.s.a.p . IIRC the Mosquito had the highest gap between takeoff speed and safety speed of any aeroplane of WWII , and more people were killed in takeoff accidents than from any other cause including enemy action

[DaveB]

By the old book sir Quote.. (iii) Do not start to climb until the safety speed of 170mphIAS (148 knots) is reached. (iv) Before raising the flaps (if used), trim the aircraft slightly tail heavy.. unQuote

Landing is equally demanding as warned in the PN's.. With the undercarriage and flaps lowered, the aircraft has a high rate of descent. Until used to this, pilots will tend to undershoot, and correction entails the use of much more power than might be expected!

ATB
DaveB

[speedbird591]

Landing is equally demanding as warned in the PN's.. With the undercarriage and flaps lowered, the aircraft has a high rate of descent. Until used to this, pilots will tend to undershoot, and correction entails the use of much more power than might be expected!

I had a feeling that he only just cleared the threshold on landing which was surprising considering the length of the runway. Perhaps he hadn't read the manual

Thank heavens we've got our dedicated team of test pilots to alert us to all this.

Ian

[Archer]

A lot of sources give a Vmca (minimum control speed - air) for the Mosquito of 180 knots. As it takes off around 130 knots there's a significant gap during which, if an engine fails, the aircraft does not have enough rudder authority to keep going straight. So you either start rolling until you hit the ground (not the preferred outcome but at this point the aircraft is flying you, not the other way around) or you throttle back the other (good) engine and aim for a flat piece of land. If you're lucky and react quickly enough (remember that you also have to feather and shut down the failed engine) you might be able to hold enough power against maximum rudder to stay in the air, but this is also dependant on the altitude and airspeed you've got available, density altitude, temperature, weight of the aircraft and the influence of your preferred deity.

That routine for the Seminole must be pretty much the same for any multi engined aircraft without prop sync. It's the way I fly all of ours on the VA anyway

You're right, a lot of light twins use similar engine/prop combinations and it is simply the aerodynamics of the props which dictate 'normal' RPMs. The Beechcraft Baron uses the same RPMs but the Piper Seneca is slightly different, using 2450 RPM for cruise if my memory is correct, I've only flown that type once so the numbers aren't as familiar as for the others.

I had a feeling that he only just cleared the threshold on landing which was surprising considering the length of the runway.

One of the three must useless things in aviation: runway behind you...

[DaveB]

Thank heavens we've got our dedicated team of test pilots to alert us to all this.

It is fortunate (or perhaps not) that due to the impending release of DG's rather stupendous Mossie B.MkIV.. I happened to have the 'Handling' and 'Limitations' section of the PN's open on my desk. It may also be a shock that much of what we've ever released as far as the FD is concerned is NOT by accident

Given that the Mossie was pretty much the fastest thing on the planet at it's introduction, it's of little surprise that this outstanding performance didn't come at a price. Jelle's summary is a good one. I can't wait for single engine testing

ATB
DaveB

[Airspeed]

Hi Dave,
Load up with a few helium balloons before you test single engine flight, we don't want to lose you mate!