DA42 TwinStar crashes at Lands End, (Merged)

[moggiee]

Originally Posted by Pilot DAR

In our (well North American anyway) society, you can do whatever you want, unless that act is prohibited by law. If the law does not say you must not, you may. Is flying any different?

I see prohibitions in the DA42 flight manual, but runway surface is not among them. I see a reference to takeoff performance for hard surfaces, but is is silent on other surfaces. By comparison, Cessna does provide a statement about takeoff performace on grass.

Pilot DAR

There is a difference between something that is legal and something that is smart.

Drinking 5 bottles of whisky in one night is legal (if you could stay conscious long enough) - but is it a smart thing to do?

[Flap40]

If you compare that video the opening shots show some apapi units. The airfield plan only shows apapi units on 34. It also shows us that there is only one windsock. Putting these together puts the wreckage in the field just to the south of the windsock.

It would need to be a very strange over-run to end up where it did.

[matt_hooks]

Latest info is that the aircraft initially attempted to take off but aborted and over ran, needing to be towed out of the mud. The pictures are the result of a second attempt at taking off.

The reason for the aborted t/o is not known as yet.

I hate to jump on pilots in cases such as this, but this one really does sound like a serious error of judgement. I hope I'm wrong, but a lot of local knowledge is pointing that way.

[Nashers]

the aircraft does look like G-SUEA. if it is, it is the one that is owned privately and has quite a few people rent it direct through the owner. stapleford do use the aircraft to teach but very unlikely to take it all the way there.

pitty as it was a nice aircraft to fly. good to hear from the reports that the pilots and pax walked away.

[Lurking123]

I would be a little careful with the 1000m figure. I think that is worst case (MTOM etc).

PilotDAR, I suggest you look a little more closely at the AFM

CAUTION

The figures in the following NOTE are typical values. On wet ground or wet soft grass covered runways the take-off roll may become significantly longer than stated below. In any case the pilot must allow for the condition of the runway to ensure a safe take-off.

NOTE

For take-off from dry, short-cut grass covered runways, the following corrections must be taken into account, compared to paved runways (typical values, see CAUTION above):
- grass up to 5 cm (2 in) long: 10 % increase in take-off roll.
- grass 5 to 10 cm (2 to 4 in) long: 15 % increase in take off roll.
- grass longer than 10 cm (4 in): at least 25 % increase in take-off roll.
- on grass longer than 25 cm (10 in), a take-off should not be attempted.

NOTE

For wet grass, an additional 10 % increase in take-off roll must be expected.

NOTE

An uphill slope of 2 % (2 m per 100 m or 2 ft per 100 ft) results in an increase in the take-off distance of approximately 10 %. The effect on the take-off roll can be greater.

[Superpilot]

Agreed, the pilot would've needed about 600m for a safe takeoff in those conditions but that's assuming use of full length and correctly applied takeoff power.

[S-Works]

It would be pretty easy not to do the performance calculations and to get half along the runway and not accelerating very well and assume they were not going to make it and retard the power. You then find your self doing 50kts on a skid pan in an aircraft with very skinny wheels......

The departure runway was 25 as I understand it which is 695m. Not a room for margin and someone fairly inexperienced on type who has not done the calculations could easily make the mistake.

[Superpilot]

Anyone know if there's an an upslope on 25? (and if so what is it), nothing on the AIP mentioned.

We were always taught to step reasonably lightly on the brakes and apply in dabs but then we were taught our IR on this plane, unlike the pilot in question.

[Lurking123]

Bose, if you are correct with a 695m grass runway being the one used, then I would suggest the chap was a little optimistic with his perf calcs.

[S-Works]

Bose, if you are correct with a 695m grass runway being the one used, then I would suggest the chap was a little optimistic with his perf calcs.

At the risk of being cynical, what performance calcs.......

The runway slopes up from the 25 threshold and the slopes down at the western end.

[Fuji Abound]

I know nothing about the current condition of the runway or the weight he had on board (so I am not criticising the decision the pilot made) but I have to say from the conditions I would expect at this time of year he has braver than me - I just dont think I would have liked the look of it in the first place, never mind getting out the book.

There is certainly no kick in the back when you open up the Theilerts. In fact there is even time to check you really did advance both throttles.

[Lurking123]

Bose, I am equally cynical. My very rough rule of thumb with a 42 is a minimum of 700m tarmac.

[Pace]

There is certainly no kick in the back when you open up the Theilerts. In fact there is even time to check you really did advance both throttles.

Fuji when I made comments about an impression I had on the only flight I have done in the DA42 the sluggish performance and acceleration was one aspect. The aircraft felt underpowered but hopefully with the new 170 hp units this will change.

The tyres felt too small yet the aircraft had long glider type wings. I also felt that the main wheels needed to be wider apart for the aircraft span.

One takeoff only but not one that impressed me. The aircraft felt more like a jet in the sense that there was no desire for it to leap skywards but more an impression of sitting there waiting for the speed to increase to rotation.

Compare that to a Seneca off grass which tries to get airbourne on every bump and before it should do and the DA42 feels very dead.

I would be interested in your comments as someone who has time on the aircraft.

Pace

[Superpilot]

Certainly rotation takes some effort compared to most aircraft in that category.

[Fuji Abound]

I also felt that the main wheels needed to be wider apart for the aircraft span.

I think the u/c width is fine. I havent discovered any skittish manners on the ground and have landed with a 30 knot crosswind and over 45 knots on the nose.

I have only operated on and off of grass on a few occasions. The grass was dry and very well kept. I would agree with you that I would be cautious about operating off short, wet and/or poorly maintained grass strips. My reasons would be the narrow tyres and the poor(ish) performance on the ground.

The aircraft felt underpowered but hopefully with the new 170 hp units this will change.

Everything is relative I guess. The diesel powered Diamonds are inevitably a compromise of a low powered engine and an aerodynamic airframe. This is even more noticeable in the 40s which seem lack lustre and "boring" whilst clearly being very efficeint and offering a reasonable cruise for a single. The 42 on the other hand is slow for a twin but feels more nimble than many other twins I have flown.

I dont think it offers the best ride when the going gets rough - so you certainly need to prepare your passengers for the worst if the conditions are bumpy. I hit my hand on the plexiglass on one occasion very hard! - but my only fault for not ensuring the belt was really tight. Mind you I definitely prefer shoulder straps.

I think its huge advantage over almost every other twin on the market is two fold - the diesels feel wonderfully smooth and quite - everyone comments on how little vibration and noise there is compared with other twins. Of course if you like glass the G1000 suite is a joy to behold for VFR or IFR ops.

Having had an in flight engine failure I can confirm that single engine ops and landing are not a problem. Fortunately I have never had a failure after take off in the 42 but have done some simulated failures at max. all up. In this configuration the climb is lack lustre until the aircraft has been cleaned up and I personally suspect that a pilot not up to speed faced with a failure immediately after rotation could well have his hands full.

All in all I think with better power plants assuming you can make do with four seats (and not the best load carrying for a twin, unless they increase the all up with more pwerful engines) its a fine aircraft. Diamond would do well to concentrate on the build quality in some areas (corrosion for example) and whilst these are largely superficial they are issues that would disappoint an owner for what after all requires only a little more attention to detail on the part of Diamond.

In fact I am sufficiently impressed that I got as close as you do to buying one (the deposit cheque was drawn!) but with the beneift of hind sight I am very glad I didnt simply because the engine issue must be resolved. I know that some people have not had any issues at all, BUT leaving that debate aside, any owner is going to want certainty over the supply of parts and longevity of such a critical component! I think the problem Diamond now have will be to convince the market that their new and untried engine will not have similiar issues once it is out in the field and, if it does, with the global recession the after market support is safe given that for a while the engine will be specific to one aircraft type and at that manufactured by the same company that makes the aircraft.

PS I would love to have a go in the Lycoming version if anyone would like to offer in time.

[Pace]

I dont think it offers the best ride when the going gets rough - so you certainly need to prepare your passengers for the worst if the conditions are bumpy. I hit my hand on the plexiglass on one occasion very hard! - but my only fault for not ensuring the belt was really tight. Mind you I definitely prefer shoulder straps.

Fuji

I have a very good friend who is an elderly ferry pilot. He was ferrying one across the north atlantic 200 miles out to sea and claims the Canopy came open. Knowing him its possible as he probably didnt close it properly
He further claimed that because of the air rush at cruise speed he could not close it.

He then stalled the aircraft and while in the stall closed it properly

I do not think the aircraft is aerodynamic as the intial tests indicated a TAS of around 200 kts at 12000 feet.

With all the bits and cooling that came to a reality of around 130 kts indicated and 155 tas which was a big downer on initial expectations.

I too would love to know how the 180 hp avgas versions perform as to me that would still be an economical but more reliable bet.

The 170 hp diesels sound far more interesting but as you said how much more reliable?

Pace

[Lurking123]

Pace, I've had 150 TAS at 95% power, 1500ft PA out of one. I agree that 200 kts is, unfortunately, a complete work of fiction. However, a true 160kts is easily achievable at 7000-10000ft with about 85%. That said, any increase in power beyond this just ups the fuel burn rate to a hideously large 45+l/hr for little payback.

PS. Never had an engine failure but spent quite a bit of time waiting for spares.

[englishal]

Another testament to the strength of these new gen composite aircraft.

I have been to Lands End and have a number of hours in the DA42. My gut feeling is that I wouldn't like to take one out of there on a good day without a decent headwind and being very light (there is no Short Field procedure for DA42).

There was an issue with the rear door on some of them. Some friends of mine were flying one when the rear door flew off. I think the initial 200+kt tests were on a model fitted with twin 180HP Avgas burners. In my experience 150-155kts TAS is a realistic cruise at about 80% power.

[Fuji Abound]

In my experience 150-155kts TAS is a realistic cruise at about 80% power.

Yes, exactly what you should expect.

I do not think the aircraft is aerodynamic as the intial tests indicated a TAS of around 200 kts at 12000 feet.

Not on the Theilerts they didnt. It is more aerodynamic that every other light twin.

My 22 is appreciably faster, and carries weight as well, it is probably more comfortable inside and gives a marginally better ride but the 42 is a lot less noisy and the extra engine is nice.

[B2N2]

Latest info is that the aircraft initially attempted to take off but aborted and over ran, needing to be towed out of the mud. The pictures are the result of a second attempt at taking off

If the above is correct....it wouldn't have anything to do with the fact that is was a DA-42.
That would have been bad in any plane.