Chipmunk sighting on M4!

[fobotcso]

Well, overhead it! Yesterday, Sat 16 Jun 2001 at precisely 1000A (Radio 2 time check).

I'm heading West with the horse boxes and Eddie Stobarts on the M4 at ground level at 70+ mph with W/wipers on fast in lashing rain just past the Membury mast and the glorious sight of a Chipmunk heading East appears; quite low in the approach to embryo CB. Overhead silhouette suggests it was Gipsy engine.

Clearly the pilot was flying into the downpour and would not have been very happy or comfortable. I wondered how far he(she) got before leaving his(her) line feature. I worried that the Membury mast would not show up to our hero. It was still standing 5 hours later when I returned, however, so all must have been well.

One thought; instead of being overhead the M4 the pilot should have been just a tad further to the right of the line feature to leave room for any possible Chipmunks coming the other way!

Anybody own up?

[This message has been edited by fobotcso (edited 17 June 2001).]

[Shaggy Sheep Driver]

Well it wasn't me or anyone else in our Chippy group. I'm surprised he wasn't offset from the motorway, since in a Chippy in poor viz you can't see much down and dead ahead 'cause the engine cowling is in the way.

BTW all Chippys have Gipsy engines - except those that some gliding clubs have butchered by fitting those nasty American engines. But then gliding clubs don't really like powered aircraft ;~))

SSD

[This message has been edited by Shaggy Sheep Driver (edited 18 June 2001).]

[fobotcso]

As I well remember SSD, especially with a big Bloggs in the front! Thanks for response; just curious - and a bit caught up in nostalgia.

[This message has been edited by fobotcso (edited 18 June 2001).]

[Skylark4]

SSD
Most Gliding Clubs have a fair sprinkling of members who are involved in power flying as well. Nothing wrong with improving the performance of a good airframe to produce a superb Tug. I have flown behind a Gypsy engined Chippy and the performance was marginal. I believe the Chippy was originally designed for a Lycoming but they had all these Gipsies no-one wanted. Would He Who Knows step forward please.

Regards

Mike W

[Shaggy Sheep Driver]

Skylark4

Yes, I used to be a glider pilot so I know about the 'them and us' at *some* clubs ;~)

I know the Chippy and its history well. Never heard it was designed for a Lyc. DH always put DH engines in their aeroplanes back then if possible.

SSD

[Firkin L]

Hey Shaggy, what do you mean "butchered"? Having flown and maintained both I don't remember anything particularly brilliant about the Gipsy Major. All I remember is having to put oil in it all the time, the mess down the underside, spares difficult to get hold of and very expensive, inferior power to weight ratio over the Lyc 360 and I am told the RAF always operated it with the Carb Heat wired in hot all the time - why was that then? I know which I'd sooner have!

[Tricky Woo]

For once I'm speechless.

[Shaggy Sheep Driver]

Why do you think we fly such vintage machines as the Chippy, Firkin L? It's becuase they have 'character', and in the case of the Chippy (unlike spamcans) they also fly properly - e.g if you move the stick a tiny tad sideways the aeroplane rolls, instantly and accurately. Move the 'steering wheel' in spamcan a similar amount - wait - and wait - and...not much happens, certainly nothing with any accuracy about it.

Putting a Lyc in a Chippy is like adding a glass and steel extension to a thatched cottage; it may make it more practical, but it's no longer what it was any more and the world is the poorer for it.

Lycs rotate the wrong way for the Chippy airframe, too. If you fit the ring mod, Gipsys use no more oil than a Lyc, and only spill it over trhe airframe during aeros (which are beyond the capability of most lyc-engined aeroplanes, so they don't suffer it. I bet Extras do!).

The RAF wired carb heat to 'hot' because unlike a Lyc or Conti carb heat on a Gipsy gives warm air, not hot air. Consequently the power loss with heat selected is small. The RAF operate out of long hard-surface airfields so the take off performance loss was not important. We operate ours out of a short grass field so we take off in 'cold' and then switch to 'warm' for the rest of the flight.

SSD

[FNG]

I heartily agree with all of the sentiments expressed by SSD. All PA28s, C150s etc should be put in a big pile and set on fire, for the general good of aviation. Their pilots should be sentenced to clean Gipsy engines with old toothbrushes. ;) ;) ;)

Only one point Shaggy: Lycomings in upside downy aeroplanes don't lob oil around. Cap 10s and Slingsbys have Lycoming AEIO-360s. The oil goes glugging through the inverted fuel and oil thingy bolted onto the back. The Bulldog has basically the same engine, but without the fully inverted thing, and that doesn't throw oil about either.

[Firkin L]

Shaggy, I can't see anything wrong with making a great aircraft even better. The introduction of the Lyc has not reduced the handling characteristics at all, probably improved them, the fact that the prop goes the other way round is hardly noticable and you get a slightly better view while taxying. The bit about the carb heat in my last post was in fact a rhetorical question to point out the vunerability of the Gypsy to icing. I'll bet the people that you know who have thatched cottages all have electric, gas, central heating, water and sewage because its an improvement over the original design. Just remember, some Chipmunks are still working aircraft who have to earn their keep - not toys, and this is the only way they are financially viable.

[Shaggy Sheep Driver]

Firkin:

We'll have to agree to disagree. To me, the farting, shaking, and banging, not to mention that lovely sound of a Gipsy that only a big-pot long stroke engine can give, are all part of the magic of Chippying. To have a bland Lyc in there, sounding like any old spamcan, is abomonation! And who'd want hand swing a Lyc? Not me!

And Gipsys are not prone to carb ice - it's very rare due the carb being mounted next to the cylinders unlike a Conti which almost demands constant hot air to avoid icing.

And the looks! Oh the looks!!! Chippies are lovely looking aeroplanes. But Lyc engined ones are, umm, shall we say "not very pretty" ;~)

SSD

[t'aint natural]

Going back to the original posting, I believe there's a farm strip just south of the M4 at Membury. I've seen an aircraft going in there while I was driving (always disconcerting, particularly for the passengers). Is it possible the Chippy was on finals?

[Shaggy Sheep Driver]

Anyone know contact details for the strip?

SSD

[Cahlibahn]

Membury Airfield, Lambourn, Berkshire. RG16 7TJ

You might try Aviation Enterprises on 01448 72224, I don't have any other number.

[ShyTorque]

FNG,

Bulldogs don't throw oil about? Oh...,yes they do! Try a bit more negative 'g'.

My boss was always making comment about the state of our ones after solo "staff continuation training" on a Friday.

Lovely stuff. Sorry about your washing, Mrs.

ShyT

[FNG]

Doubtless a fair comment, ShyTorque, I'm such a wimp that I've only done positive (actually would like to try getting a bit more daft but the aircraft's owner (who is not Brenda) gets a bit prissy about that sort of thing).

[Dan Winterland]

The main advantage of the 160HP Lycoming over the 145HP Gypsy engine for glider towing is the finer prop of the Lycoming which gives you a better rate of climb than the coarser Fairey-Reed prop of the Gypsy. The extra 15 HP don't really feature.

The disadvantage of the Lycoming mod is that you can't (legally) turn the aircraft upside down. Also the Gypsy is far more robust than the Lycoming.

[UhrCleared-Takeoff]

Shaggy Sheep Driver,

The landing strip at Membury is owned by Southern Sailplanes Ltd. Last time I was there, the runway was in quite poor condition, but there is a small grass strip adequate for a PA18

I don't think it is available for general use, apart from aircraft visiting the workshops (M3)and of course gliders!

[Shaggy Sheep Driver]

Final nail in the coffin of the Lyc engined Chippy, methinks!!!

You can't aerobat it!

Well, since the only point of flying a Chippy is to sample that great handling, fitting a Lyc turns it into a straight and level machine, only fit for towing gliders - and even that must be a bit marginal with modern heavy glass ships.

Thanks to those who gave details of the Membury strip - but there appear to be 2 - the old airfield which I think is N of M4, and a 'farm strip' S of M4? Anyone know?

SSD

[Rod1]

I think you can put a Lycoming in a Chippy and turn the aircraft upside down. There was a mod, which included adding a big Lycoming and making the aircraft a single seater. I think the result was a supermonk and it was very competitive when it first appeared.

[UhrCleared-Takeoff]

The M4 cuts straight across the old airfield, the useable bit being on the south side of the motorway.