This column comes to you from 32,000ft - seat 7F on the Friday afternoon KLM flight from Amsterdam to Toulouse to be exact. I am, you could say, winging it at the moment, though not in the manner of those New Yorkers who ended up on an unscheduled cruise down the Hudson river the other day, standing on wings that had conspicuously failed to keep their crate in the air.

Of course, it subsequently became clear that the plane's sticky-out bits were in perfect working order, and that the problems of the flight came down - in every sense - to the fact that an Airbus A320 may be the most powerful food slicer made but it's certainly not the most durable, failing spectacularly to chomp its way through some avian gristle.

Yet the plane's impromptu ingestion of a flock of starlings or suchlike did bring to mind an article I once read in an in-flight magazine which explained that a modern jet engine is designed to withstand a simultaneous bird strike of six pigeons.

This is quite fascinating. I appreciate that modern aeronautical design techniques are probably heavily reliant on computer modelling and other whizz-bang theoretical tools, but I like to think that this claim was based on experience and had been verified by experimental trials.

As an occasionally nervous flier, it would be reassuring to know that Rolls-Royce or Pratt & Whitney do actually employ someone to throw pigeons into their engines, ratcheting up the doo-count until the power plants give up the ghost in a cataclysmic explosion of molten metal and badly singed feathers. It's all very well saying you've achieved new levels of safety - a term that might require a more flexible definition for the pigeon-fancying fraternity - but nothing nails down the claim like a spot of empirical test data.

In which context, I'm also led to wonder just how much work designers of the Jaguar XF really did on a bonnet that is engineered to open if the car happens to strike a pedestrian. Disappointingly, this feature is not about eviscerating passing jaywalkers and spitting them out the back of the car, rather about raising the rear of the bonnet to flick them over the top.

How thoughtful. Before you know it, pedestrians will be queuing up for the sheer privilege of being mown down by the XF and calling out their thanks through mouthfuls of gravel as they are jettisoned through the nearest hedge. But has Jaguar really tried this one out on live volunteeers? Can it say with genuine authority that being clobbered by an XF is a markedly more enjoyable experience than being struck by something more mundane?

The interior of the Jaguar flagship is one of the wonders of the automotive age. Some curmudgeons might dislike a keyless entry and start-up system that denies them their Freudian thrill of poking things into holes, and there is something a tad too theatrical about the way the air vents and autobox selectors twirl into life, but the ergonomics of the rest of the interior are pretty-near perfect.

Our test car, the 2.7 diesel, came well loaded with extras from the Taggarts Motor Group's Maryhill Road outlet, but even the base version cossets its passengers in sumptous surroundings, and keeps them entertained with a touch-screen console that controls every conceivable function of the car.

It whisks them along at an agreeably brisk rate as well. There are more powerful engines in the XF range, including the just-announced and eye-wateringly rapid five-litre 503bhp XFR version, but the one we had never felt it was thirsting for oomph, a surefooted rightness that probably owed much to the slick operation of the six-speed auto box.

Its ride and handling also seemed well matched to the V6 lump that was purring happily beneath the bonnet.

That poise is also evident when the XF is standing still. Some critics have argued that it has sacrificed headroom to maintain coupe-like lines, while others say the pay-off has been in the other direction.Getting stick from both camps suggests jaguar has probably got the balance right.

The company has often seemed just a touch too keen to exploit its own illustrious history, a kind of retrophilia that has meant it could not make a car without cramming it with styling cues from the past.

In that regard, the XF is a great leap forward, a strong and confident statement of intent without the yes-I-do-own-the-road-actually brashness of some of its sector rivals. In a market dominated by some seriously impressive vehicles from BMW, Mercedes and Audi, it can certainly hold its own.

Jaguar XF Engine: 2.7-litre, V6 diesel (others available) Top Speed: 143mph 0-60mph: 7.7 seconds Economy: 37.6mpg combined CO2: 199g/km Road tax band: F (£210 per year) Car Supplied By Taggarts Motor Group, 262 Maryhill Road, Glasgow, G20 7YD www.taggarts.co.uk Tel: 0141 332 7777 Back-page Driver SMALL IS BEAUTIFULLY GOOD VALUE As used-car values have been following a graph more like a cliff than a curve of late, drivers looking to insulate themselves against the chill winds of recession might be interested to know that Britain's slowest depreciating car last year was the Toyota Aygo, pictured below. According to Parker's, the respected price guide, a buyer who shelled out for an Aygo last year will have lost a measly £1515 since - or about £4 per day.

Unsurprisingly, the Aygo's sister cars, the Citroen C1 and Peugeot 107 - which are effectively the same vehicle with different badges - also do well, taking second and fifth spots respectively.

All the cars in this year's top 10 are in the compact class, a reflection of the fact that more and more drivers are trading down to smaller and more economical models. THE STORY IS O And what do you do with the dosh you saved on that modest little Aygo? You spend it on an immodest number plate, of course. And one of the most sought-after plates of all will be up for grabs when the DVLA holds its first registration auction later this month.

The plate 1 O has a reserve value of £10,000, although it is likely to reach many times that figure. Over the next few months, the DVLA will also release 220O, 3 O and 4 O. Credit crunch or no credit crunch, the registration market still looks buoyant.

Last month, retired Surrey businessman Rob Harverson bought 1 RH for a staggering £247,000 at DVLA Personalised Registrations' final auction of 2008.

Prudent Scots might be interested to know that one of the lots in the next auction is HAM 155H, with a reserve of just £900. AMERICAN BEAUTY As if US car makers didn't have their troubles to seek after going cap-in-hand to Washington recently, the word from the Detroit motor show is that their efforts have all been shaded by Audi's Sportback, the luscious new stretched coupe from the German manufacturer. The combination of sleek sport hatch and five-door versatility is likely to provide the dominant theme for Audi designs over the next few years.