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Posted

Might be fine if you have a 80% scale Superfortress or something very complex. Having a very qualified person (singular) should be the situation except in some very special circumstances. Increase the risk of injury/death and pay more and attract more attention. You put the performance down a lot too with our weight limit aircraft. Makes everything have to be that much closer to optimum to work on the day. Nev

 

 

Posted

I don't see a problem, provided the obvious intent (ie a relevantly qualified and experienced pilot) is adhered to. There are many people out there building their own experimental planes who have quite limited flying experience.

 

In those cases I believe it will amount to a net reduction in the risk of the first flight, not an increase.

 

You will find that there are highly experienced pilots who will be willing to do this and accept the risk, though the ones I've met will certainly charge you accordingly (and fair enough too). Alas some builders will also be made acutely aware if their build quality and documentation is not up to scratch, as such pilots are usually very fussy about the experimental aircraft they're about to hop into! While that might be damaging to the ego, I don't think it will be damaging to safety. Quite the opposite.

 

 

  • Agree 1
Posted

So who's in charge? You have yourself and an expert you think you will need or will be of help. Don't like the possible scenarios. The builder will traditionally try to save the plane above most other considerations. That has been the motivator for a lot of "less than Best" decisions on test flights. Nev

 

 

Posted

For the sort of test flying we do, I don't think it is a good idea. If the builder is not competent to fly the first test flight, than it should be flown by a competent test pilot. For later flights it is a good idea, but only to ensure the builder can safely fly the plane. I see no reason to have two people flying the first flight, which must be a situation where something could go wrong, so the pilot should be competent. Once the plane has been proved to be safely flyable, then it may be a good idea for the builder to have someone to hold his hand.

 

I have done some test flying and having someone else to worry about on the first flight would not suit me.

 

The worse case scenario is test flying a single seater that you havn't flown the type before. Nobody was going to let me fly their Corby Starlet to see how it went, so my first flight was completely new to me. Funnily I was more keyed up flying the first flight in my RV4, even having had transition training in an RV7.

 

One of the things that wories me is test flying a plane I havn't built, means that I don't have as much knowledge of the systems as the builder does. Also things can be counterintuitive, such as switches being down for on, or a pull to increase throttle.

 

 

Posted

With an uncommon or complex plane the knowledge of the test flying pilot IS an issue, regardless of his/her total experience, IF he/she didn't get involved with the construction or had an extensive course on the "in's and Out's" on everything that matters. This is no different from doing weeks of study in ground schools as part of a conversion course on a complex plane, and that is normal, but you still don't just charge off solo on your first flight, unless it's a single seat Jet or scale fighter or such.

 

Builders have been spending thousands of hours constructing the aircraft and most times haven't been doing a lot of actual flying at the same time, because of time and cost constraints. Often they are low total hours pilots as well. A lot of thought has been put into reducing the risks involved with this phase of the planes flying.

 

Things like NOT having an unproven engine at the same time as an unproven plane, and using the services of another pilot are recommendations. We don't want a one size fits all approach to this matter either. Nearly every situation would be different in some way, but at the moment it is more hazardous than it could perhaps be. Nev

 

 

  • Agree 1
Posted

The last thing that needs to be happening on a test flight, especially a first flight, is for the 'experienced' pilot to be conducting 'instruction' of the inexperienced builder pilot. And this is what's likely to happen, despite all the best intentions. Creates a most unnecessary distraction and that's not smart. Not a good safety approach at all. After several flights, and the 'experienced' pilot has sorted out the flight characteristics, and established all systems are safe - then is the time for the 'inexperienced' owner/builder/pilot to be included.

 

happy days,

 

 

  • Agree 2
Posted
After several flights, and the 'experienced' pilot has sorted out the flight characteristics, and established all systems are safe - then is the time for the 'inexperienced' owner/builder/pilot to be included.happy days,

Even if this was allowed after initial proving, say five hours, then fly the next five dual with an instructor, before flying off the remainder of the tweny five hours would be a big improvement on what many builders do now.

 

 

Posted

Sorry I don't understand the purpose of the 5 hours Dual (after 5 hours). The test process has a list of parameters to check and record. If any flight characteristic is not satisfactory you would rectify before proceding with the 25 hours "proving". The recording could be well achieved by voice recording and transfer later on the ground, I suggest,as you wouldn't want to be distracted from the primary aim of flying the plane, early in the piece, particularly. Nev

 

 

  • Like 1
Posted

Is there any RAAus requirement for pilots who are going to do test flying to get any training, or oversight into their capabilities?

 

 

Posted

What's the situation when it comes to single seat aircraft? If I build on of my designs, I feel it should be my risk and no one else's.

 

I think this would apply to a new design 2 seat plane. The 'other' would be no more familiar with it that the builder/designer.

 

 

  • Agree 3
Posted

The more "different" the more the builder would be the logical person to do the flying (All other things being equal). Single seat makes no difference to the present situation where there is only one person on board by the rules. RAAus planes are "assumed" to be simple in concept, so most systems should be fairly basic, requiring minimum training/application. I didn't say NONE. Pilots MUST be familiar with everything on the plane they fly. Any thing less would not be acceptable under any SMS. Nev

 

 

Posted
Is there any RAAus requirement for pilots who are going to do test flying to get any training, or oversight into their capabilities?

Hi Yenn,

 

Basically no, they give some suggested experience and hours in command prior to conducting a test flight in the recent Flight Test Guide on page 5.

 

Some parts of the guide I don't agree with, but I will be using it as a reference for my Sonex test flights. Its based on the FAA's AC 80-89 which I have also printed out for reference.

 

http://www.raa.asn.au/wp-content/uploads/2014/05/Flight-Test-Guide-Issue1.pdf

 

Regards

 

Tony

 

 

Posted
One of the things that wories me is test flying a plane I havn't built, means that I don't have as much knowledge of the systems as the builder does. Also things can be counterintuitive, such as switches being down for on, or a pull to increase throttle.

To me personally that's not a very convincing argument. There are many factors which can influence who might be the most appropriate person to test fly a plane. In the big wide aviation world outside recreational and amateur-built aviation, the reality is that the test pilot almost never built the thing.

Also I would question if the plane has been built counter-intuitively such as switches or throttles working against normal aviation conventions (and in those cases the conventions have very good reasons for being the way they are), whether it should be flown at all. Perhaps it would be best for the builder to just fix it so that it makes sense, but who is going to tell him this?

 

 

  • Agree 1
Posted

One series Vickers Viscount had the fuel switches one way and another model had them the other way. Crews were multi endorsed. What a set up for an accident. Being certified they were never modified to any compliance model.. .

 

Of course in the big aviation world the test pilot would never build. The fact is MOST pilots never build an aeroplane Homebuilt is a separate concept that some people will never accept. I don't believe that the previous CASA CEO ever got his head around it either., or accepted that "ordinary people" could service their planes. I agree there ARE many factors to be considered in the matter of the test flight. and choice of pilot to conduct it.

 

The general view is the builder should seriously consider the use of another specialised TEST pilot.. It should not be mandated as it's not a "one size fits all solution".. . Recency, experience, on type (OR SIMILAR) and broad spectrum of knowledge as well as superior (hopefully) flying ability to average are relevant. In this instance being an instructor would only be secondary if any direct bearing on choice. There might also be some aircraft not many would offer to test fly, unfortunately...Nev

 

 

  • Agree 1
Posted

Quite a few good points on this thread. I have a couple of comments, for what they may be worth:

 

Firstly, test flying is a quite different skill set to that of a normally competent aviator. An experienced pilot without actual test flying experience, will normally have experienced many aircraft types - but most of them will be certificated types, which means that whilst they will have different "feel", they will all behave in essentially the same general way.

 

You will no doubt remember the first time you drove a car other than the one you learned to drive on; it felt very different. But when you get to your sixth car, you hardly notice the differences, because under the superficial "feel" they all act very much the same. It's the same with aircraft - provided they are certificated; and this leads people to have an unconscious expectation that all aircraft inherently behave similarly. You do NOT normally find yourself in a car with, for example, negative caster; and to somebody who has never experienced something of that sort, it would come as a very rude surprise.

 

The reason all certificated aircraft behave essentially similarly, is that somebody sweated blood to make them behave that way. They do NOT necessarily do so until their fangs have been drawn. The reason we have operating limits and centre of gravity limits is to define the range of such parameters within which the aircraft does exhibit acceptable behaviour. With a new prototype, especially an amateur-designed one, these limits are not defined, and it is the test pilot's job to determine what the safe operating limits are. Usually, a professionally designed aircraft will have defined structural limits and these will have been worked out for a "structural design" centre of gravity range; but the handling and stability limits are still very much the responsibility of the test pilot.

 

So experienced test pilots usually know a few "tricks" to let them spot marginal or negative longitudinal or directional stability before they allow the aircraft to get into a situation that is unrecoverable. There are other things that need to be approached in small increments, such as the damping of airframe oscillations.

 

Secondly, flight testing is essentially a matter of data collection. The last thing you want is an experienced pilot who will bore a hole in the sky for 45 minutes or so, and then come back, hitch his trousers, spit downwind, and say "She's Beaut!". You need to plan each flight according to the item of data you want; and configure the aircraft to achieve that; then go and perform precisely the planned test and nothing more. In other words, plan the flight and fly the plan.

 

Thirdly, a test pilot must know when to stop. If you lack sufficient knowledge to identify a hazardous condition before it gets dangerous, you will not survive.

 

Flight testing demands precise control of weight and balance. It is not uncommon the weigh the aircraft, with the test crew aboard, before and after a flight. At the very least, the aircraft's empty weight and CG must be determined accurately, at the outset, and each test loading condition must be at a known centre of gravity position. If you do not know how to do that accurately, do not attempt to test fly an aircraft.

 

Flight testing also demands precise control of airspeed - which means that the airspeed system errors need to be determined as early as possible in the test program - just as soon as the engine has been proven to cool adequately, in fact. See CASA AC 21.40 for suitable procedures for ASI system calibration.

 

If you are talking about a kit-built aircraft for which the CG limits and other operating limits are already defined, then the flight testing is essentially equivalent to the "Production flight test" of a certificated aircraft, and its purpose is not to sort out fundamental design issues, but to ensure that the aircraft is in trim, and that everything works properly. That is a task that any relevantly experienced aviator can reasonably tackle. However, the Lancair 235 that I experienced was a kit-built aircraft, and it did have fundamental stability problems; so an LSA kit or a kit based on a certificated aircraft, can be a very different proposition to one that merely meets the "51%" rule.

 

 

  • Agree 1
  • Informative 1
Posted

Most of your recorded data would have little meaning unless you had accurate airspeed readings but they are rarely achieved in the majority of basic examples of what we are talking about. (Unfortunately). Look at the Auster for example. Always under reads at the low speed end of the indication,. but it does it consistently and there fore the indicated speeds YOU get used to work for you once you have a little time on them and fly them at LOW speed for a while to understand the feel. (Basic seat of the pants stuff.)

 

Wjth an unknown plane on the first circuit you carry speed margins, but you might do some upstairs work first in some situations, unless something else changes your mind. (like a high engine temp). You really do not KNOW what to expect initially and build up confidence in the plane as it "proves itself". You need a definite planned programme as Dafydd says but you must be flexible depending upon changing circumstances.

 

I should mention choice of aerodrome. If possible, give yourself the best chance of coping with events going pear shaped. Have a witness with a car and extinguisher and an open gate or two. Have alternate landing points all around ideally, not over a built up area.. This could be a big topic..... Nev

 

 

  • Like 1
Posted

I'm still puzzled why anyone would actually think this step is a bad one. The ruling from the FAA is not mandatory. If you want to test your homebuilt solo, you can still do that under the old provisions.

 

What it does is provide a legal basis for people who are amateur-building from kits to have an experienced 2nd pilot with relevant qualifications on board for flight testing to help mitigate flight testing risks. It makes special mention of the increasing complexity of kit-built aircraft. This is not some idea that someone came up with on a whim. This is a two year old recommendation from the National Transportation Safety Board. The FAA then did a review of 10 years of historical accident data relating to Phase 1 testing in the homebuilt community before releasing this ruling. The advisory circular gives substantial guidance on the issue, including determining the PIC and so on.

 

If the homebuilding community decides to ignore NTSB recommendations and FAA safety studies of Phase 1 flight testing, it risks shooting both its own feet clean off.

 

 

  • Agree 2
Posted

No one is suggesting that this be ignored . There are downsides to it as well and the type of relationship hinted at but not spelled out in detail, in the cockpit is far from normal with sport planes .. With the training situation normally it is the INSTRUCTOR who is PIC, unless otherwise negotiated, and made very CLEAR. There is no such thing as a two man crew in this type of activity If you alter this you have to be clear just what is required in all possible situations Not knowing just who has command, is a disaster. Look at the recent Virgin ATR effort. Haven't you ever flown with two management pilots? Some of the worst operations I have known happen there, even though they are highly trained

 

Unless you really can justify the extra person it is only another person to be injured or killed in a risky situation. That is also the reason you do the 25 hours, solo. The plane is still under test, even though at that stage it is more of an endurance and proving demonstration, having been cleared of the requirements to conform to performance criteria and document such details initially. Nev

 

 

  • Agree 2
Posted
Sorry I don't understand the purpose of the 5 hours Dual (after 5 hours). The test process has a list of parameters to check and record. If any flight characteristic is not satisfactory you would rectify before proceding with the 25 hours "proving". The recording could be well achieved by voice recording and transfer later on the ground, I suggest,as you wouldn't want to be distracted from the primary aim of flying the plane, early in the piece, particularly. Nev

I wouldn't presume to be competent to test fly my plane, but after five hours dual, post test I would like to fly off the remaining 15 hours solo. As things stand I am going to have to buy five or so hours in a school plane just to get current again since I only have a bit over thirty hours total time.

 

 

Posted

CRM and 'democracy' on the flight deck is quite a distance from test flight decision making. A type experienced pilot in the RHS sounds like a safety enhancement, but it fails to satisfy the Australian Phase I requirement that a full test program be flown in no less than 25 hrs, (40 hrs for 1st of type. Once the aircraft is signed off - then 'instruction' - of whatever form, can be commenced. IMHO, any distraction should be avoided, and that especially means a talkative owner/builder.

 

happy days,

 

 

  • Agree 1
Posted
I don't see a problem, provided the obvious intent (ie a relevantly qualified and experienced pilot) is adhered to. There are many people out there building their own experimental planes who have quite limited flying experience...

True, Dutchie. After years in the workshop and precious little time flying, I finally achieved my life's ambition. I eventually had to admit to myself that I'm not a test pilot.

 

 

Posted

The issue is resources.( time and money). Builders spend it on building.the aeroplane. It is the predominant thing in their lives for years. Naturally they want the ultimate experience of flying it for the first time. When it turns out bad it is a real tragedy. Building it is one thing .. flying it is another. Nev

 

 

  • Agree 3
Posted
Most of your recorded data would have little meaning unless you had accurate airspeed readings but they are rarely achieved in the majority of basic examples of what we are talking about. (Unfortunately). Look at the Auster for example. Always under reads at the low speed end of the indication,. but it does it consistently and there fore the indicated speeds YOU get used to work for you once you have a little time on them and fly them at LOW speed for a while to understand the feel. (Basic seat of the pants stuff.)Wjth an unknown plane on the first circuit you carry speed margins, but you might do some upstairs work first in some situations, unless something else changes your mind. (like a high engine temp). You really do not KNOW what to expect initially and build up confidence in the plane as it "proves itself". You need a definite planned programme as Dafydd says but you must be flexible depending upon changing circumstances.

I should mention choice of aerodrome. If possible, give yourself the best chance of coping with events going pear shaped. Have a witness with a car and extinguisher and an open gate or two. Have alternate landing points all around ideally, not over a built up area.. This could be a big topic..... Nev

Nev, if you do not understand what data you should be looking for, you definitely do not know enough to attempt to test fly a new prototype. If you're interested in the subject, download FAA AC 23.8 (I think now at issue c or possibly d). It will give you considerable bed-time reading.

A competent test pilot can usually make a fair qualitative assessment in considerably less than one hour's flying. That's cheap insurance, I would have thought. Getting all the numbers takes quite a bit longer; and when you're starting from scratch, there's almost always some development to be done - which means the overall task may take up to around 25 hours for a "simple" aircraft - or possibly more, if some difficult problem shows up.

 

 

Posted

Dafydd, I always refer to the requirements when I do something, so if it appears that I don't please be assured. I don't want to labour a lot of detail issues in general discussion. The principle is what matters to me and that is what I try to get across. It's a style thing. it might appear I simplify things. in discussion. I try to make my presentation for all the audience Strict requirements I do at the time I have to. as we all should. Nev

 

 

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