Prang at Starke Field

[jakej]

You're correct Alf, this is part of the reason I let my L2 & therefore RA Aus membership lapse now leaving kindergarten permanently. For the stirrers - good luck.

 

 

[Love to fly]

The RV6 has a known and well-documented lack of elevator authority at low speed/power conditions. In the case of engine-out, it cannot flare at less than about 65 kts. - it flies straight into the ground, and if not the modified version, then folds up around the cockpit and crushes the occupant/s' skulls Look at the fatality statistics. Later VANS aircraft do not have this problem. And, absolutely, VANS aircraft do not unilaterally have elevator authority problems.

.

Hi, help me out here. Where is this documented? I fly an RV6A and haven't noticed this when landing, or heard of it before. Happy to admit my ignorance but would like to learn more.

 

 

[bexrbetter]

All these vehicles are perfectly safe if maintained and operated correctly.

Mate that's just flat out not true in the real world.

 

Everyday highly experienced people in all types of highly maintained machinery in every corner in the world die or seriously injured through unforeseen circumstance.

 

accident

 

 

 

1.

 

an undesirable or unfortunate happening that occurs unintentionally and usually results in harm, injury, damage, or loss; casualty; mishap:

 

automobile accidents.

 

2.

 

Law. such a happening resulting in injury that is in no way the fault of the injured person for which compensation or indemnity is legally sought.

 

3.

 

any event that happens unexpectedly, without a deliberate plan or cause.

 

4.

 

chance; fortune; luck:

 

I was there by accident.

 

5.

 

a fortuitous circumstance, quality, or characteristic:

 

an accident of birth.

 

6.

 

Philosophy. any entity or event contingent upon the existence of something else.

 

7.

 

Religion. being born to parents who believe there's actually a god.

 

 

[Nightmare]

Mate that's just flat out not true in the real world.Everyday highly experienced people in all types of highly maintained machinery in every corner in the world die or seriously injured through unforeseen circumstance.

 

accident

 

1.

 

an undesirable or unfortunate happening that occurs unintentionally and usually results in harm, injury, damage, or loss; casualty; mishap:

 

automobile accidents.

 

2.

 

Law. such a happening resulting in injury that is in no way the fault of the injured person for which compensation or indemnity is legally sought.

 

3.

 

any event that happens unexpectedly, without a deliberate plan or cause.

 

4.

 

chance; fortune; luck:

 

I was there by accident.

 

5.

 

a fortuitous circumstance, quality, or characteristic:

 

an accident of birth.

 

6.

 

Philosophy. any entity or event contingent upon the existence of something else.

 

7.

 

Religion. being born to parents who believe there's actually a god.

Well if you are going to include all those other factors as well, you agree with me that all those vehicles are on par with one another as far as safety goes.... if these other factors worry you, you may as well roll yourself up in a little cocoon and hibernate away from the rest of the world.... of course accidents happen, but they are greatly reduced and the consequences reduced if they do happen, when operating and maintaining those vehicles correctly.If it is not clear, I have no opinion on the crash at the start of this post, that is up to the investigators. My thoughts and wishes are with those affected and injured by it.

 

 

[Oscar]

Hi, help me out here. Where is this documented? I fly an RV6A and haven't noticed this when landing, or heard of it before. Happy to admit my ignorance but would like to learn more.

Ltf: suggest you look at this article: SDS EM-4: Aircraft. Para 6 is a simplistic explanation of the elevator authority problem: his comment about 'not enough energy to flare' actually refers to elevator authority: without the prop wash, at 'normal' final approach speed, there is not enough airflow over the elevator to pull the nose up and slow the descent rate.

 

I cannot find the accident report on a fatal RV6 crash in Australia, though I know the investigator well and remember it. It was an engine-out forced landing into a clear, long, smooth and flat paddock; the evidence showed that it had flown into the ground at a normal approach speed. indicating a failure to be able to flare to arrest the descent. The fatal result was a structural problem; early RV6's without strengthening of the cockpit side members will in such a crash fold back and crush the occupant's heads: this was verified by the autopsy. I would like to stress that VANS has rectified this problem on later models, you should NOT take it that I have a vendetta on VANS aircraft. However, pursuit of the accident reports does show that the RV6 has a noted high accident rate. They are aircraft to be respected and flown accordingly - and absolutely, by no means, unique in that!.

 

May I respectfully suggest that you investigate this characteristic - but at a very safe height. Give yourself a lot of room, cut the engine, and then try a 'normal' final to flare profile. (by 'normal, I mean, maintaining the speed you would use in 'normal' condition). If the reports are correct, you will find that when you simulate the flare, your aircraft will not respond to the elevator movement by an attitude change, a reduction in speed and a reduction in vertical descent speed.

 

IF none of the above conditions happens, then the 'conventional wisdom' is wrong.

 

 

[Love to fly]

Thanks for the reply. Google hasn't found me much documentation. I've done many glide approaches (idle engine) in the last 8 years and never had an issue in the flare.

 

As soon as the weather cools down I'll go and have a play at altitude.

 

 

[djpacro]

Ltf: suggest you look at this article: SDS EM-4: Aircraft. Para 6 is a simplistic explanation of the elevator authority problem: his comment about 'not enough energy to flare' actually refers to elevator authority: without the prop wash, at 'normal' final approach speed, there is not enough airflow over the elevator to pull the nose up and slow the descent rate.

Your comment is quite a bit different than that reference which states: "Elevator authority will be reduced with no power so the flare will take longer to execute and speed will bleed off faster with no residual idle thrust from the prop." That and the associated text is consistent with the airplanes that I normally fly, looks normal to me. When teaching people in the Decathlon I alert them to the reduced height needed to commence the flare during a "glide" approach. In a Pitts the best glide speed is higher than normal approach speed so, like that reference, it is important to maintain that speed right down to the flare. I see many people letting the speed decay at 100 ft or so as warned about in that article.

I have very little time in an RV, just interested.

 

http://www.jasonbeaver.com/rv7/articles/How%20To%20Land%20An%20RV.pdf has similar statements to the reference above.

 

 

 

[poteroo]

Thought it time to summarise my experiences in 20 yrs test flying and instructing in RV4, 6, 6A, 7, 7A, 8, 8A, 9, 9A, and 10. Not yet in a 12 or 14.

 

1 - think about these numbers. We try to make 500fpm approaches in most aircraft - either by using less flap +/- power, or more flap + power. Whatever it takes to give you a more or less constant angle of approach. Most RVs will glide at around 70KIAS clean and give you about 600fpm descent rate - higher with a CSU operating in fine pitch due low power. RV pilots need to adjust their approaches to the magic 500fpm for consistency.

 

2 - the 9 and 9A have longer wings, more flap area but only 30deg deflection at fully extended. Over the fence at 60KIAS and closed throttle is perfectly safe in all but 15+ crosswinds. Plenty of elevator command remains and they are definitely the easiest/safest of all the RVs. The VANS factory staff love the 9 series.

 

3 - all the other RV's that I've flown have 40deg flap settings and this does give you a fairly steep approach with closed throttle - steeper if you have a CSU! Preferably hold 60/65 and a touch of power so that you stabilise at 500fpm on mid final.

 

4 - the early 6 and 6A had smaller rudders and less elevator command. Quickly learned to either keep 65-68KIAS down to the flare (throttle closed)...and avoid highish roundouts. Safest has always been to hold a touch of power on through the roundout and close it , (judiciously), in the flare. In the tailwheel 6 the most reliable landings are, (surprise,surprise), done from a relatively low height flare to a full stall in the 3 point configuration. A bit more 'squirrely' on bitumen, but a delightful feeling of achievement on grass! Wheeling the 6 takes a whole lot more skill and it's something that requires a heap of practice. The technique I teach is for another thread so will stick to the lower speed + near full back stick types. In the 6A - it's even easier than the 6: once in the flare and in ground effect, slowly close what little power remains and increase the angle of attack with more elevator input. You will touch down on the mains with the nosewheel well up. Keep it there! A really good practice lesson is to continue to hold the nosewheel off until you feel the elevator losing command - then add just enough power to allow you to hold the nosewheel off and you can taxy the full length of the runway like that. Teaches you a 'feel' for your pitch inputs in an RV.

 

5 - in all of my time in RV's, I've never scraped the aft undersection of a wheel spat, nor heard of anyone who has. What does happen with RV's is that the small tyres and infrequent utilisation of most aircraft, allows tyres to deflate. This allows chafing of the tyres on the folded under lower edges of the wheelspat and gives you an alarming smell of burning rubber on taxy. Pump them up to 40psi, or if you don't have a gage - to no more than 75mm of 'flat' on the ground and very little sidewall bulge. One of the most important maintenance items .

 

 

6 - RV aircraft are very sensitive in pitch. Pilots need many hours adapting their control stick 'feel' so that they have reduced it down to using just 3 fingers and their wrist locked down against their inner knee. The aircraft can't be landed lightly and with a delicate touchon of mains until pilots have practised and practised their power x attitude basics. And after you master the art of smooth safe landings - try formation in your RV. That requires a whole new control 'feel'. Then after that - try low level in the RV, because without mastery of your pitch inputs you will never be safe either close to the ground or your mates in formation.

 

In summary, RV's are fantastic aircraft which have to be flown with skill and with due regards to the laws of aerodynamics. Don't skimp on either good instruction or on diligent pracrice.

 

happy days,

 

 

[rgmwa]

For what it's worth, I flew a 7A for a while when returning from Bunbury to Serpentine. Compared to my 12, I found the 7A had about the same feel in pitch, was a bit more sensitive in roll (shorter wings) and a bit heavier on the rudder than the 12. The 12 probably flies more like a 9 and is easy to land at around 50-55 KIAS over the fence. Best glide is 63 KIAS. Unlike the other RV's, the nose wheel on the 12 is the same diameter as the mains and the nose leg is relatively rugged, which should help on grass and rough ground.

 

rgmwa

 

 

[Love to fly]

Thought it time to summarise my experiences in 20 yrs test flying and instructing in RV4, 6, 6A, 7, 7A, 8, 8A, 9, 9A, and 10. Not yet in a 12 or 14.,

Great post. Thanks.

 

 

[bexrbetter]

the consequences reduced if they do happen,

How is the "consequence" reduced? - you're staring at the consequences, i.e a flattened plane on it's back, and the cause has zero bearing on the result for these people, and many others past and present, of not having roll over protection.

 

What good fortune there was no fire involved, sadly that has not always been the case where people have not been able to get out.

 

For your own interest, Google "flipped over aircraft" .. I'm sure most of them have a reasonable, and valid avoidable reason for having flipped, but it doesn't changed the fact that there they are laying on their backs.

 

If you're really brave, Youtube Roger Williamson's death (Formula 1), it's the one that drives me to have roll over protection.

 

 

[djpacro]

Great post. Thanks.

We must do some formation stuff next.

[Happyflyer]

Final report is out. Pretty clear about what happened. https://www.atsb.gov.au/media/5772702/ao-2017-001_final.pdf

 

 

[facthunter]

Pretty high sink rates and airspeed. If you aren't stabilised go around. You don't even have to let it contact the ground. Go around and have another try. Nev

 

 

[facthunter]

I don't know how the plane maker can be responsible for getting high on the approach and the pilot stuffing the nose down. Of course I agree with the fact some (most) U/L's are harder to fly and GA planes are more sorted out. This is a "management of the situation", situation. Not everyone should try to fly planes and you will even find them in Airlines. Stress can aggravate it perhaps caused by an unusual situation. Some people who have done BAD things have said. "I don't know WHY I did THAT. I have been told innumerable times never to do it but I did it.(under pressure). Extra training and evaluation even self evaluation.... Good stuff.. but you have to be very honest with yourself, or it's a waste of time. Nev

 

 

[aro]

A couple of things about the chart in that report...

 

• The VSI appears to be lagging. It shows a descent for several seconds after the altitude is zero so that is unreliable as an indication of the actual rate of descent at touchdown.
   
   
  
• Airspeed is shown in TAS so IAS might be lower
   
   
  

 

 

1.3 times stall speed is a good starting point to determine approach speed, however aircraft characteristics might show something higher is better, e.g. low aspect ratio wings where drag increases rapidly as speed reduces. I haven't flown a RV, I don't know what the recommended approach speed is.

 

It is obvious to me there is a problem with the RV nose gear, based on the number of collapses & flips. They aren't all solely the pilot's fault. I believe there was a RV nosegear collapse on takeoff at Avalon.

 

I like RVs, but would only own a tailwheel RV-6-7-9.

 

 

[facthunter]

The strength of the RV nose gear depends on the engine installed in some instances. The nose gear is never the strong point of any aeroplane. It's never meant to take the whole load of the plane and there is a structurally limiting sink rate that can be tolerated by the gear generally. So does it when the plane starts to porpoise. IF you are HIGH & FAST you have excess energy to get rid of. A Tricycle U/C with a damaged nosewheel assy is not controllable once the remnants dig in. Landing (touching down) at above recommended speeds is accompanied with a wheelbarrowing tendency that generally comes to a bad end. Nev

 

 

[aro]

Nose gear is never the strong point, but is there any other aircraft that ends up on it's back with the frequency of the RV 6-7-9A? I know a couple of aircraft that have had nosegear collapses, I am trying to think if I personally know anyone with an A model who hasn't... (maybe it's me?)

 

According to the report, the video showed the main gear did touch down first (seeing the actual video would be very interesting).

 

 

[frank marriott]

This strip is about 3000ft long but has trees on both ends (outside the property fence). For anyone with limited bush strip experience it can give the false impression of being a lot shorter resulting in the occasional "different " arrival.

 

An actual obstacle gives a different mental picture to the theoretical one on P charts.

 

 

[poteroo]

Proper training & testing is the key, it's too easy to get a license especially in RA these days .

Disagree with this. It really depends on the flying school ensuring all the competencies are met. I personally don't instruct any differently in RAA or GA, and the student has to meet the same in either category. After all - flying is flying, and the numbers on the aircraft should not mean a completing pilot is better or worse than another.

 

is obvious to me there is a problem with the RV nose gear, based on the number of collapses & flips. They aren't all solely the pilot's fault.

Disagree. There is a worldwide problem with RV pilots not being trained to fly them safely though. I believe it goes back to the instructors themselves not being really competent to train other pilots on more advanced types. CASR 61.385 applies.

 

GA instructors really do need to have reasonable time-on-type before actually instructing. Unfortunately, only 61.385 spells out anything to guide you. As an example - would I conduct competency training in a Lancair or Glassair? Hell no - I don't have any PIC time on them, and despite being legally able to, I don't. Another example that comes to mind is with instructors conducting tailwheel endos, and formation endos, - when they have bugga all PIC time on/doing them.

 

RVs are generally being flown too fast on approach, and too slow on initial climb. More on this in previous post.

 

you can't build in enough safety features for the low end drivers

Agree. In principle, over-engineering should never be an alternative to training in good technique. But it seems, from the published accident reports, that poor handling is the major causal factor. I also get to hear of other RV 'incidents' which can be traced back to poor technique.

 

No surprises with the ATSB report though. Runway Loss-of-Control accidents will continue to unfairly dog the RV series aircraft for so long as owners and pilots fail to fly them competently. And that puts pressure on insurers to raise the rates for the rest of us.

 

 

[Oscar]

Nose gear is never the strong point, but is there any other aircraft that ends up on it's back with the frequency of the RV 6-7-9A?

I don't follow RV accidents with any much interest, but I know of one brand of aircraft that does tend to play 'dead ants' quite a bit. As it happens, I own one of these, and have been repairing it for several years now following an overturn as a result of a hard landing following an EFATO ( not mine!) - and as regular members of this forum will know, I am a staunch ( some would not unfairly suggest I am a 'tragic') 'defender' of the brand. However, fairness suggests that the facts should not be ignored.

 

I refer to Jabirus. You don't have to do much searching on the web to find piccies of Jabs displaying tendencies more usually ascribed to attention-seeking young ladies with few (if any) inhibitions and possibly an elevated level of PCA.

 

A few years ago, I did a private 'research' project on light aviation accidents and found a disturbing proportion of landing incidents had resulted in overturn. I don't recall Vans 6-7-9 aircraft being over-represented. Of Jabs. there were a-plenty.

 

As a result, I intend to add five-point harnesses to my own aircraft. That may seem to be anticipating 'closing the gate after the horse has bolted'. However, bear with me here a moment.

 

The ATSB report on this accident includes comment on 'serious injuries' to the occupants - which I suggest can only be a result of the intrusion of crash damage to the occupant area.

 

Without wishing to be macabre, pretty much the worst sorts of injuries are injuries to the cranium and the spinal chord. In a low-wing, bubble-canopy type aircraft, those are the most vulnerable areas for injury in an overturn - and the u/c configuration makes no difference to that vulnerability.

 

Despite the many incidences of Jab. overturns, there have been remarkably few occurrences of serious injury. That is a result of the fact that the Jab. cabin structure is an extremely strong 'capsule' protecting the occupants - and there are other high-wing aircraft with similar characteristics, though the Jab. is somewhat famously 'tough' in occupant safety. Bex's post #61 encapsulates my own concerns.

 

Overturn in a landing incident is a definite risk for all light aircraft flyers. I would not be looking at the VANS aircraft as a risk beyond others due to that possibility - but I WOULD be looking at any low-wing, bubble-canopy type aircraft as an increased risk of serious injury IF that happens.

 

 

[Nobody]

It is obvious to me there is a problem with the RV nose gear, based on the number of collapses & flips.

And yet the NTSB did an analysis that found that "the nose gear strut had sufficient strength to perform its intended function."

 

 

[Yenn]

This loks like the same as many other landing accidents. Too fast and lacking in ability to control the plane. If you are 106 times stall speed and descending at a high rate, the mains are going to hit and the nose keeps going down, if the nosewheel survives this you bounce back into the air, stall and down comes the nose again.

 

I watched a GA plane, not RV do this at Old station, bounced once, bounced twice and bent the tips of the prop 90 degrees, bounced third time, bent the prop tips again 90 degrees, demolished the nose wheel and turned upside down. Sad thing was this was the second time the pilot had done it to that plane, but I think he now has difficulty getting insurance.

 

When you follow the accident reports that are available it is clear what the cause of the majority of accident is and it is not poor aircraft design, nor is it mechanical failure.

 

Poor piloting due to poor flight reviews may be a factor, but i would think that pilots are on their best behaviour at that time. Another factor could be that RV pilots may not do the review in an RV. I just did mine in a Piper, because my RV isn't set up with full dual controls, nor can the passenger transmit on he radio.

 

With my Corby no instructor can fly with me and they have to tell me what they want me to do and I go off and demonstrate my ability.

 

 

[kaz3g]

. ..... I flew a Zenith 701 (High Wing) from home... I always put it down on the main wheels first, only allowing the nose wheel to touch the ground when the speed was low enough.Frank.

I hope that is how everyone lands their tricycle aircraft. It's not just RA that are prone to nose wheel issues; more than one of the C100 and C200 series has ended up with a buckled firewall from a nose wheel arrival and quite a few more have done a quick excursion off runway for same reason.

 

Kaz

 

 

[kaz3g]

From the "Secret of the Machines" by Rudyard Kipling...

 

But remember, please, the Law by which we live,

 

We are not built to comprehend a lie,

 

We can neither love nor pity nor forgive.

 

If you make a slip in handling us you die!

 

We are greater than the Peoples or the Kings—

 

Be humble, as you crawl beneath our rods!-

 

Our touch can alter all created things,

 

We are everything on earth—except The Gods!

 

Kaz