CF-18 fighter jet crashes in northern Quebec - Pilot safe

[Sf2]

I asked you first

and since I'm a helicopter pilot, I'll explain it in the context of the affect of cold air temperatures on the orafice in the P3 stage during rapid throttle applications in both manual and automatic fuel control modes......after you answer my question.

*EDIT*  Google cut and paste not allowed

 

[Strike]

mcleod,

Your remark about helos being useless in firefighting just goes to show your inexperience in the field.   A water bomber would be hard pressed to douse   a firs that is sitting on the side of a steep mountain whereas a helicopter (which is run by a private company most of the time in both BC and Alberta) is the perfect sollution.

As for the compression stall -- at 1500 feet with two engines, a single engine compressor stall isn't as tragic an event as you make it out to be.

Why don't you define what a compressor stall is, and what effect it has on an aircraft in a
pitch-up position (or pitch-down) - MacLeod

Had it happen at that altitude on a single engine jet.

 

[jmacleod]

You asked first - for those that might be reading this stuff, let me start out with an example of
compressor stall the movie "Top Gun" illustrated the effect of compressor stall. Cruise in
his F-14 flew into the wake of another F-14 and the engines on his aircraft stalled and stopped
-in the real world there are a number of factors in combination to cause excessively high
internal ambient temperatures, caused by a reduction of airflow into the compressor. This can
cause, engine surge and or compresser stall, (the compressor stops) when the airflow over the
compressor blades exceeds the aircraft's angle of attack(pitchup, pitch down) - compressor
stall has been around since Whittle invented the jet (turbine) engine. The RAT on the CF-104
was designed to restart a stalled engine, by drastically changing the angle of attack - using
the unit, located on the starboard side of the fuselage to pump air into the compressor. The crash
of a 747 cargo aircraft at the Halifax International Airport might have been caused by compressor
stall on takeoff - MacLeod

 

[jmacleod]

Use of helicopters in forest fire fighting will continue of course - there is a company in Pennsylvania
converting USN surplus "Sea Kings" for forest fire supression right now, but the bucket brigade
really can't do the job of say the Air Tractor 802, a bug sprayer that designer Leland Snow has
upgraded to surpress fires - Air Tractor Olny Texas, on the net. I think Okanagan Helicopters
are flying Air Tractor 802's in BC now on the fire projects, and they are also used in France. NS
Forest Protection uses helicopters for bucket dumping, and do a good job but are limited -
they got a lot of credit several years ago for saving most of Clayton Park (housing and condo's
but they got lucky - the wind shifted. MacLeod

 

[Strike]

let me start out with an example of
compressor stall the movie "Top Gun" illustrated the effect of compressor stall.

If that was a good example of what a compressor stall does I would be dead a few times over already, along with most of the Snowbirds, manu students that went through Moose Jaw on the Toot and are now flyinf the Hawk, and any fighter guy that has gone 1 v 1.  Compressor stalls going through the jet wash of another aircraft are very rare -- as are the "flat spin" that your example of choice produced.  Bad example.

 

[jmacleod]

Strike: I replied to your post and your points are well received, however my post appears to have
vanished - but the really important aspect of the loss of the aircraft is that Captain Marks survived
if you are aware, there are operational aspects of the CF-18 (CF-188) which remain classified and
cannot be discussed on this forum, however the aircraft remains high in my estimation. Appreciate
you remarks. MacLeod

 

[Sf2]

Mcleod

1)  Know your audience - you're speaking to pilots who fly turbine engined aircraft

2) 

in the real world there are a number of factors in combination to cause excessively high
internal ambient temperatures

  actually, high internal temperatures is a symptom of a compressor stall, not a cause.

3) 

This can
cause, engine surge and or compresser stall, (the compressor stops)

  The compressor doesn't stop, it slows down a bit, and looses efficiency.

4) 

when the airflow over the
compressor blades exceeds the aircraft's angle of attack

  I'm not sure what you're really saying here.  Airflow cannot exceed the angle of attack of an aircraft.  Airflow determines the angle of attack, specifically defined as the angle between the relative airflow and the chord line of the airfoil (no, i didn't pull that off google).  It is possible for an aircraft to achieve an angle of attack that causes turbulent airflow to enter the intake.

5) 

down) - compressor
stall has been around since Whittle invented the jet (turbine) engine. The RAT on the CF-104
was designed to restart a stalled engine, by drastically changing the angle of attack

  The RAT did nothing to change AOA.  It was a small turbine that powered essential systems for engine restart. From the Lockheed site - There was a ram-air turbine (RAT) in a pop-out door on the lower right side of the fuselage, just behind the nose gear, to provide electrical and hydraulic power in case of systems failure.


6) 

The crash
of a 747 cargo aircraft at the Halifax International Airport might have been caused by compressor
stall on takeoff - MacLeod

From the Aviation Safety Network - 17 DEC 2004 Wrong throttle setting cited in probe of 747 crash at Halifax
The investigation into the accident of an MK Airlines Boeing 747 cargo plane at Halifax, Canada in October is focusing an improper throttle setting made by a member of the crew

 

[Inch]

You asked first - for those that might be reading this stuff, let me start out with an example of
compressor stall the movie "Top Gun" illustrated the effect of compressor stall. Cruise in
his F-14 flew into the wake of another F-14 and the engines on his aircraft stalled and stopped
-in the real world there are a number of factors in combination to cause excessively high
internal ambient temperatures, caused by a reduction of airflow into the compressor. This can
cause, engine surge and or compresser stall, (the compressor stops) when the airflow over the
compressor blades exceeds the aircraft's angle of attack(pitchup, pitch down) - compressor
stall has been around since Whittle invented the jet (turbine) engine. The RAT on the CF-104
was designed to restart a stalled engine, by drastically changing the angle of attack - using
the unit, located on the starboard side of the fuselage to pump air into the compressor. The crash
of a 747 cargo aircraft at the Halifax International Airport might have been caused by compressor
stall on takeoff - MacLeod

WTF, over.

MacLeod, I know short final asked you to explain a compressor stall, but I'm unsatisfied with your response so standby for a little bit of an education with respect to compressor stalls.  

A compressor stall doesn't mean the compressor stops, it means that there's been a disruption of the airflow into the compressor, things like salt ingestion or taking a bird in the intake could cause an engine to compressor stall. Symptoms of a compressor stall can include, popping (like a machine gun), fluctuating Ng (or N1 depending on which aircraft you fly), and increasing T5 (or TOT/ITT/etc) due to the reduced airflow into the engine for cooling. This is all accompanied by a loss of thrust which in certain regimes of flight can be catastrophic. Now, your reaction in response to a compressor stall can vary from aircraft to aircraft, but in my experience, reducing the load on the engine by pulling back the throttle or lowering the collective seems to be the general response.

As for an engine compressor stalling due to high AOA, I've never once heard of that happening, the wing should stall long before the compressor and no, the wing does not stop moving when it stalls.

 

[jmacleod]

The F-104 had a problem with high angle of attack causing compressor stall, and compressor
stall remains a problem for high speed turbine engines as you all know - a bird strike certainly
can cause a major problem for a funtioning turbine engine. In any event, AIB will come up
with a conclusion about the Bagotville aircraft shortly I would think. There is a lot more to
the 747 freighter crash than a cursory initial observation by TC - but it is hard to believe that
a fully loaded freighter flown by a very experienced Captain would have an improper throttle
setting - freighters that go into Halifax rarely go empty, pick up usually what is value added
seafood (lobster,scallops) which have a shelf life,quickly,and are on their way. Some of the
cargo operators here and in Halifax think that the load (tractors among other items) may have
shifted, others think the fish product may have been improperly weighed, plus loss of power
for whatever reason. That TC Report should be published soon. MacLeod

 

[aesop081]

jmacleod,

I will let my pilot companions take care of the technical details here but even if the   crew was experienced ( halifax crash) it does not mean that they are imune to simple errors.    There was a crash in florida where the aircraft's crew flew into the ground when none of the cockpit crew were looking outside.   They were fixated on a light in the dashboard !!

For the technical stuf on turbines, i would reconsider your position.   As a backender, it only took a cursory look at the AOIs and the emergency procedures manual to figure out you are to lunch.

Putting a bit of info in your profile wouldnt hurt either......

 

[Zoomie]

JMacleod - how about filling in your profile a little more - it might make your comments easier to swallow...

You seem to spout alot of CASR DND-101 junk - are you affiliated with that website?

The Halifax 747 crew obviously wasn't experienced enough - maybe that South African flight training didn't cover the lessons on Weight and Balance - initial findings are that the big bird ran out of runway before achieving Vr.

I think enough has been said about compressor stalls...  It's good to see that my 32A compadres are on top of the ball when it comes to this topic - the CC-115 compressor is pretty robust and we rarely see the conditions that may preclude a stall.  We're more concerned about hitting the water or mountains than about our compressor hiccupping.

 

[jmacleod]

You are kidding of course. What crash in Florida are you referring to? An entire aircrew fixated
on a light on the "dashboard" - was it a warning light for instance? what was the name of the
operator? what type of aircraft, turbine, turboprop, reciprocating propeller equipped engines
-I  answered a question about compressor stall off the top of my head, but I suspect that the
rebuttal came out of a textbook - easy to be an expert when you check in the book first.The
point is, as of now an unknown factor, or factors caused a CF aircraft to go down, so we are
all speculating. Whatever the cause, hopefully it will be defined and the problem resolved.
End of story as far as I am concerned. MacLeod

 

[Sf2]

agreed with Zoomie - we could go on all day comparing Subject Matter Experts opinions on compressor stalls, and those who think they may have seen it in a movie once.....

Bottom line is that at any level, be it base commander or internet junkie, it's inappropriate to assume or conclude ANYTHING when it comes to this incident.  THe best thing that came out of this is a pilot who was there, got out, and will be able to describe first hand what happend.

And to say my rebuttal was out of a text book?   Sorry buddy, but I make the big bucks because I'm supposed to know this stuff off the top of my head.   So when I DO hear popping, rising ITT, and fluctuating N1, its always COLLECTIVE/AIRSPEED.....REDUCE, HEATER SWITCH.....REPOSITION.   If condition persists AFFECTED ENGINE......IDLE, Land as soon as practical.

as for the "dashboard light", I believe it was a faulty gear indication light, where all crew were fixated and troubleshooting, and allowed the aircraft to impact the ground.

 

[Sf2]

here you go mcleod - if you're interested, the cockpit voice transcript of this "Dashboard" light problem  http://www.airdisaster.com/cvr/cvr_ea401.shtml

 

[mdh]

From wikepedia....

Eastern Airlines Flight 401 crashed into the Florida Everglades on the night of December 29, 1972, causing 101 fatalities. It was the first crash of a wide-body aircraft.

The plane, registered N310EA, was a four-month-old Lockheed L-1011 and was carrying 163 passengers and 13 crewmembers. Flight 401 left New York's JFK on Friday, December 29th, 1972 at 9:20 pm, en route to Miami International Airport. At the controls were Captain Robert Loft, 55, a verteran Eastern Airlines pilot ranked 50th in senority at Eastern, and first officer Bert Stockstill. The flight engineer was Don Repo.

At 11:32 PM, Eastern Airlines flight 401 began its approach into Miami International Airport. When co-pilot Stockstill had looked at the landing gear indicator, the green light that identifies that the nose gear is properly locked in the 'down' position did not illuminate. This failure has two possible explanations: either the gear was not down, or the light was not working. Either way, this is considered to be a small issue for pilots, as the gear can be lowered manually. The pilots recycled the landing gear and still didn't get the confirmation light.

The crew became fixated on the light allowing the plane to lose altitude until the accident - also was made into a movie "Ghost of Flight 401" with Ernest Borgnine IIRC.

cheers, mdh

 

[aesop081]

as for the "dashboard light", I believe it was a faulty gear indication light, where all crew were fixated and troubleshooting, and allowed the aircraft to impact the ground.

Thats the one ( i was lookign for a better word than dashboard but for some reason i had a mental blockage...good thing i wasnt flying today !), must have been during a very dry part of HPMA.  My point was simply that even experienced aircrew fall victim to simple errors.  Just ask my tac hel freinds here if they like to have both the pilot and the NFP having their heds in at the same time !!  I know that when i did OJT at 403 sqn they sure didnt do that !!

And i beive that it was YOU, jmacleaod, who was doing the speculating when you said that in your opinion it was a bird that brought the 18 down.  Members of this board who fly for a living have presented other pssibilities because you made a quick assumption based on nothing of value.  You then proceded to argue about compressor stalls with people who's job it is to know.....WTF ? Whats next, you are going to argue with me about identifying and classifying emiters with ESM ? Maybe you would like to argue about cabin fire of unknown origin procedures with me ?

But then again we don't realy know who were are talking to do we..........blank profile !!

From wikepedia....

The crew became fixated on the light allowing the plane to lose altitude until the accident - also was made into a move "Ghost of Flight 401" with Ernest Borgnine IIRC.

cheers, mdh

Yup....when we talk about it, the tower controler said "Eastern 401, how is everything going" ( or something to that effect).   Maybe if something more assertive had been said ( eastern 401 check altitude or eastern 401 climb imediately) this could have been prevented....my $0.02.

 

[Sf2]

Snowbird just crashed, suggest we give this up and wait for the final investigation, and pray for the Snowbird families.

 

[Strike]

Heard the snowbird pilot was sent to hospital with minor injuries, so I figured I'd add a little to this thread...

it is hard to believe that
a fully loaded freighter flown by a very experienced Captain would have an improper throttle
setting

It's also hard to believe that an Air France jet would continue to land 4000 feet down a runway when he is too fast, and onto a wet runway, but he did, instead of electing to go around.

As pilots, we may think we are perfect (some of us may actually be  ), but we are not, and are still prone to mistakes.

 

[Zoomie]

...I  answered a question about compressor stall off the top of my head, but I suspect that the
rebuttal came out of a textbook - easy to be an expert when you check in the book first...

Sorry partner - you're playing with the big boys now - it's easy to be an armchair pilot, a lot tougher to be a professional one...

 

[Cloud Cover]

I think enough has been said about compressor stalls...   It's good to see that my 32A compadres are on top of the ball when it comes to this topic - the CC-115 compressor is pretty robust and we rarely see the conditions that may preclude a stall.   We're more concerned about hitting the water or mountains than about our compressor hiccupping.

LOL, be sure to keep your eyes off the dash board lights. [see aesops post].