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Gentlemen, I have not seen so much commotion since "Left throttle, Right
Stick", for those of you who remember that!
Following my earlier email, I have been asked to comment on, and reply to, a
number of questions and points. I will try to do so one by one:
1. BMA Production Numbers. I was asked to justify my statement about the
production rate. I probably did not express it very well when I said that
it was comparable to Chelton's, when I really meant that it was high enough
to be credible relative to theirs. Sorry for the poor wording. At the time
I just knew from what I observed (and the time I had to wait for delivery)
that it was significant. I therefore checked it out with Malcolm Thomson of
BMA. To date they have sold over 300 systems and delivered over 200. Since
they cater exclusively to the experimental/homebuilt market, BMA obviously
cannot know how many are flying; their best estimate is around 100. If you
check their website you will see photos of a number of flying examples,
including an L-39 and a Gazelle. The reason that you do not see many
Lancairs flying with their system is simple; we all waited until it was
recommended by Lancair Avionics early this year, so they are mostly still
under construction.
2. Certification. The BMA system is not certified by the FAA. While FAA
certification certainly gives some assurance of quality, the lack of
certification does not mean the reverse. After all, the DoD gave up on Mil
Specs some time ago, replacing them with individual requirements for each
application (and relaxing many to save cost) with no obviously disastrous
effects (but there are no more $2,000 hammers, or at least we hope not).
Understandably the FAA has not relaxed requirements designed for commercial
passenger aircraft. I do not fly such an aircraft. My main concerns relate
to vibration, temperature ranges and translational errors. As the L-39
exceeds Lancair performance, and any helicopter vibrates continuously, I
feel some justification for fitting the BMA system to my aircraft. I then
will fly it for a lengthy period and gain experience of it in actual
operation before it ever sees a cloud. I will cross check it regularly
against an alternative data source as standard practice. I hope you all do
the same, whatever your instrument system! I then have an integrated
display system which provides vastly more information than any standard
instrument set, and to my mind increases safety.
3. Electro Magnetic Compatibility (EMC). EMC is certainly a vital
consideration. However I really do not agree with Brent that the reason
that laptops have to be turned off during airliner take off and landing is
interference with the navigation and communication equipment. Laptops are
put away for take off/landing so that they do not hinder emergency egress.
If they caused interference, they would be banned throughout the flight.
EMC is certainly why cell phones are banned at all times, as they emit EM
radiation, and can in rare cases cause interference. If you install any
EFIS in your composite aircraft, and fly it for 100 hours, you will know if
there is a significant compatibility problem. It won't appear just because
you go IMC. As with all these things, first try it in controlled
conditions.
4. Flight test. Kirk, I absolutely agree that I should have some evidence
of the system's performance under flight test. I got that from a
professional source at Lancair Avionics, namely you. You stated in print
that,
a."Chief Pilot Peter Stiles and Greg Richter took off in the company IV to
put the EFIS/One through the paces. After they returned, Peter walked into
my office to report the test flight. "I couldn't fail the system," Peter
tells me. I questioned him further about the test and couldn't believe my
ears. The Blue Mountain EFIS/One performed flawlessly.
b. "Based on the testing standards we put these guys through, the accuracy
of their system and their level of support, we will be offering the BMA
EFIS/One to our customers."
c. "We are extremely pleased that Blue Mountain Avionics has been able to
correct earlier issues and demonstrate a system capable of passing our
rigorous tests. Their AHRS system meets or exceeds standards normally
associated with higher end equipment. The Lancair tests have proven that
the EFIS/One AHRS system is ready for the high speed aircraft that Lancair
sells."
In addition you personally told me that the BMA system had passed all your
tests, and that included passing some tests that the Sierra (now Chelton)
system could not. There was no mention anywhere of your new opinion that
the BMA equipment is only suitable for VFR. I am puzzled that you appear to
have changed your mind since speaking to me while at Lancair.
4. Lancair Policy. It is simply not true that Lancair is not recommending
the BMA system. I spoke to them yesterday, and they confirmed that they are
still representing BMA and offering the EFIS One for sale. I also
understand that their system was removed from the company aircraft when they
had finished flight test, and was returned to BMA at BMA's request for an
upgrade.
5. Cost and Certification. I repeat, for those of us operating on real
world budgets, the cost of a certified Chelton system puts it totally out of
reach. I believe that the certified system costs about $70K (I have not
checked, and apologize if I am way out). I paid $12,800 for my BMA system
(the price is now up to about $15K), and the autopilot costs another $3,500.
That is comparable to the cost of the conventional units that I can replace.
Chelton originally proposed an autopilot, but never delivered it, and sent
refunds to their customers. I would love a new certified Chelton system,
but not when that will double the cost of my aircraft; it just is not even
thinkable.
Kirk is selling the Chelton system to the experimental market at a reduced
price, I believe around $50K.. What some of us had not previously realized
is that, as I understand it, the hardware in the experimental version of the
Chelton system is different from the certified version. It is not just that
they do not include the paper certificate with the box, the unit is
physically different and has not been certified. So it appears to me to be
neither better nor worse than the BMA system in this one respect. Just
because it looks like a duck, and quacks like a duck, that does not mean
that it will float!
6. Man Machine Interface (MMI). I absolutely agree with Brent that you
need to be very careful about cockpit design and how to handle an EFIS
failure. A while back, I was the test pilot on a number of trials on
cockpit workload and visual disorientation using electronic cockpit
displays. There are actually 2 significant issues:
a. Which one is correct? If you have conflicting attitude information on
2 attitude indicators, you need to be able to quickly work out which to
trust. You can either fit a third data source (T&S or T&B), or train
properly, so that the rest of the scan tells you the whole picture, and so
which AI to use.
b. Cockpit Layout. Too many people put the standby AI right next to the
EFIS display, which seems like a good idea, but I believe is undesirable.
As Brent says, it is very hard to ignore conflicting data, especially in a
compelling format. I have put my EFIS on the left of the panel, the radio
stack in the middle, and a set of mechanical standby instruments off to the
right. That way, I can still easily cross reference the instruments, and
yet minimize the distraction from whichever data source is showing false
information following a failure. You should also keep a stick-on gizmo
handy to cover up a faulty instrument; it really does help.
Finally a personal view. I do not particularly like messages promoting
systems in which the correspondents have a personal or financial interest
(and I discount them), but I recognize your expertise and your right to do
so, and they can sometimes provide useful insights. However I really object
when the message on our private List disparages a competitor, usually
without their knowledge or any opportunity of a reply. In my opinion, that
is not the purpose of our List. Declaring an interest before doing so does
not get you off the hook, to my mind. By the way, judging from private
email messages to me, some other people feeI the same, but avoid posting
comments to avoid being "flamed".
OK, I have had my say. I think that you have all heard quite enough from
both me and the Chelton marketing department, so I do not intend to return
to the subject. However I would like to hear from the silent majority. Do
you agree, or am I full of BS (either opinion is valid)?
Jerry
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