Bizarre comments in Pilot magazine flight tests
 

I've just read a new flight test in Pilot of the RANS S-7 Raven:

Flight Test: RANS S-20 Raven - Flight Tests - Pilot

A very impressive review, except for one bizarre comment:
I thought it so odd, that I signed up to post a comment, asking them to expand.

Following that, I started reading other reviews, starting with aircraft I have flown. First the Bulldog (Flight Test: Scottish Aviation Bulldog - Flight Tests - Pilot), where I came across this odd, highly unlikely statement:
Is this just wishful thinking or poor editing?

I wonder what they are smoking sometimes when they write these flight tests! Well spotted. You wont get any bonus points for expressing an opinion with the magazine.

Probably not, which why I posted here as well. :E

What on earth is wrong with Dave Unwn's statement. 1.3 x Vs1 for a final approach speed is ridiculous in any VLA or three axis microlight that I have flown. That extends to a Nipper or a Turbulent. There a insufficient margin over the stall and such light aircraft are badly affected by wind gradient or gusts. Dave's advice is excellent IMHO.

Agreed due to low momentum in these type of aircraft.

G-KEST,

You've explained my complaint. If the review had contained a sentence or two, along the lines of your response, then I would have been happy with it.

The article is supposed to be a technical review, not a primer in English euphemisms. Many readers probably wouldn't understand the reason for his bizarre statement.

I cant decide if IFT is concerned that the review a) gave insufficient explanation of the advice on approach speed, or b) used an obscure phrase to illustrate the likely outcome?

Which is it?

Both seem perfectly reasonable to me. The technical advice is correct (for reasons already given) and "it'll end in tears" is a commonly used phrase meaning that something will end badly - at least in British english it is, and Pilot is a British magazine.

(I rather like "It'll end in tears". It is reminiscent of a Victorian nanny scolding Master Heston for some nursery misdemeanour before threatening a spanking with the hairbrush... Ooooh I need a cold shower now)

It ain't British English it's English.

Is the full quote. Given there are approximately 300 registered training organisations and many older instructors that seems pretty reasonable - why do you consider it bizarre?

Odd. I found the remarks re the Raven self-explanatory. Surely its obvious that approaching slowly in a hi-drag lo-inertia vehicle is a bad idea, and if something "ended in tears" then it didn't end well?

For those of you with little or no experience of flying, especially LANDING, a F/W microlight - The 1.3 Vs works well provided that at that speed you come in & over the fence with power right through to touch down.

Obviously that's simplified, for the pedants here one uses reduce power to maintain the correct speed till in some cases only inches off the ground.
The landing remains very short and (nearly) always satisfyingly smooth.

That avoids the otherwise loss of airspeed and falling the last 6 feet onto the ground, if one attempts the regular GA a/c glide for the last part of finals. The exception is with loss of the donk when one dives much faster to use that kinetic energy for ensuring enough momentum remains for round out.

If the OP is really worried about such nuances in a general article in a magazine - not the handling notes for that 'plane - then a nice letter to them would likely have some beneficial effect or alternatively generate a bog standard disclaimer to all articles !

mike hallam. (Rans S4 pilot)

India

We had a thread before on this 1.3 times the stall is just a figure it could be 1.2 or 1.4 or even higher
It is really a sensible margin over the stall which power off gives enough energy to transit from the approach profile to the landing configuration.
As others have said if you have a high drag machine 1.3 times the stall in a given configuration might not be adequate

So what do you come over the fence at Mike, about 30kts? That really wouldn't give you much excess energy in a draggy aircraft that only weighs about 600lbs. (I've not flown an S4, so happy to be corrected).

Turbulent approach speed - by the book - is 55-60 knots with a stall speed of 38 knots. This gives you 1.44-1.58 stall speed, and seems about right.

I agree - high profile drag, high induced drag low inertia aeroplanes like that do not want a 1.3Vs approach. 1.5Vs for a 600kg aeroplane, and 1.7Vs for a 300 kg aeroplane I'd say is indeed about right.

One further observation - aircraft in that class, and Rans in particular often suffer substantial low speed linearities in the ASI, and that can potentially require a still larger *apparent* margin.

Dave Unwin is an experienced pilot who has flown a wide variety of very light aeroplanes. I'd expect him to fully understand that, and that seems reflected in his comments.

Shame I can't afford one - it looks great fun.

G

Both my Rans S6 behaved impeccably at an indicated 50mph approach speed until over the threshold, then just throttle back and try to get to the far end of the runway. Lands itself.

Just my twopence worth...

Many years ago I owned & flew a Pegasus-XL flexwing microlight.

Approach and landing were easy in good conditions. At the right point in the circuit the engine would be brought from cruise to idle, simultaneously the bar was pulled in, the target airspeed was 45 to 50 mph on the approach to give plenty of energy for the flare and landing. Keeping the airspeed up also made roll control just that bit more positive.

Due to the low weight and high drag the float was very short as was the ground run. The stall speed one-up was around 25 mph so I was usually doing 1.8Vs to 2.0Vs on the approach right up until I flared for the landing.

On one flight my ASI failed which was pretty much a non event.

The point is that the approach/landing technique on that aircraft was very different to that from heavier aircraft such as a PA28-161 which I also flew.

PPD

But what was the CAS margin above Vs?

G

I recall being told that the proper name for a Rans S6 was Rans 55, because it does most things at 55mph. However, cheap non certified instruments provide only a rough guide. Obviously I never stalled her close to the ground, but when doing the annual permit renewal flights, I stalled at around an indicated 39mph. So, by maintaining an approach speed of no less than 50 mph I had about 10 mph in hand. This is in still air and I increased approach speeds up to 55/60 mph as wind conditions warranted. (Strongest crosswind landing was 17 knots) I guess that computes to 1.28Vs - 1.53Vs, subject to the vagaries of the cheap instruments. Incidentally, it bimbled along happily in the 50-70 mph (indicated) speed range.

I fail to see the problem here.
This is a review written by a magazine employed "test pilot". It is not a technical report by a manufacturers test pilot for the purpose of writing the Pilots Operating Handbook. I can see nothing wrong with using currently common phraseology.
If the POH had stated, "this thing handles like a wet sponge unles you use a fist full of throttle on final", then there may be cause for concern.