Angle of Attack when landing.

[dfarrow]

The 744 has a FPA , Flight path angle indicator , which is switchable . We were not taught how to use it on the conversion course , and with 4 trips a month or so , not enough sectors, time or energy to experiment safely on the approach . The ex Airbus boys delighted in using it , but being old , grey , and an ex- tractor driver with wings. I needed proper explanation and practice . Have always found on every a/c if a certain attitude is maintained , with a certain power setting ,then a certain performance is obtained .
The trick is to make sure the attitude and power are correct for the performance that you want .

ATB dave f .

[Chris Trott]

I agree. The AoA indicator and FPA are best reserved as a secondary indication in normal situations, but they're a nice cross-check/sanity check to make sure that you're "in the groove" when you get stabilized on your numbers. There's been at least one or two "close calls" I've seen reported in the past on the NASA ASRS report where the FPA or AoA gave an indication to the crew that something wasn't quite right. One case involved a load not correctly placed that didn't show itself until approach (heavy fuel on departure masked the aft CG), another helped diagnose/solve a flap indication issue as they were able to use the AoA indication to ensure a safe lift reserve during approach when they weren't sure of the actual position of the flaps.

[cstorey]

If you want a classic example of how over-reliance on indicator devices ( rather than flying in accordance with the usual principles ) can lead to catastrophe , have a look at January 2015 AIB bulletins , where a Citation approaching FL 430 over Birmingham, UK , stalled and executed 5 360 degree rolls in succession, losing 15000 feet in the process , before being recovered with bent wings. What had happened was that the alpha protection vane had jammed, and thus inattention by the single pilot led to a stall. Incidentally, I hadn't realised that to reach these levels out of harm's way from commercial traffic, a Citation gets into that nasty corner where Mmo( or at any rate the normally achieved Mach no ) is very near to Vs i.e. it was down to about 130kts IAS to achieve climb of 500 ft/min and even then the IAS was continuing - undetected - to decay

The link is http://www.aaib.gov.uk/publications/bul ... 380cr_.cfm

and should be compulsory, if chilling,( particularly the pics of the wing ribs ) reading !

[Dev One]

Phew!!! What colour were their underpants.....

Real coffin corner reading, my simple analysis of some of those traces indicate to me that he was in a spin - see the compass heading trace.

Too much reliance on computers & software design, I'm old fashioned don't like PFD's! Not only that one always seems to be flying on the edge of a razor blade in these modern types....are 737's etc just as bad?
Keith

[Chris Trott]

At the extreme high end of their cruise altitudes, yes, they get fairly close to a coffin corner. If you look at AF447, I think they only had like 15 knots to play with at that altitude and weight. While it is an issue, when properly managed and monitored, it's not that big of an issue. It's when you get into situations like above where it's single pilot and they get distracted. The thing here is that I think the mechanical failure of the AoA vane is the bigger issue here because it caused several other items of data for the airplane to be unreliable and thus didn't give him the whole picture of what was going on, especially since the AoA "Unreliable" flag was not properly being displayed when the AoA system failed giving the impression to the pilot that all systems were working normally and he could continue operating the aircraft in a normal manner.

[Nigel H-J]

Hello all and very many thanks for your replies to my question, I have to say from reading all your replies it has, to all intense and purposes, made me think even more seriously when flying FSX rather than just treating it as take-off - flight - followed by an arrival!!

This is true of many turboprop airplanes as an excessive pitch (above 5 degrees on landing) can result in much more damage to the landing gear and the airplane than accidentally touching the nose at the same time as the mains.

Chris, I have found on many occassions when flying the Twin Otter (depending on C of G loading) I have actually touched down on all three wheels!
but your explanation has really helped as has everyone else's.

So many thanks to everyone who contributed to this thread as it now means that I am taking more into account the A of A on approach and making sure that my airspeed is also correct for the type of a/c I fly, for instance I used to fly the the Piper Carenado in at 80Kts on final approach to a small airfield such as Wickenby but now fly it at the recommended speed of 89kts which means the A of A is by far much better with not a hint of nose up.

I will in future read the a/c manuals before a flight!!

Many thanks again.

Nigel.

[cstorey]

Which Piper is this, Nigel ? 89 kts sounds awfully fast to me - in the days when I taught IR on a Seneca we generally flew any 2 engine approach at 80 kts as far as I remember - somewhere I still have the pilots' notes

Edit : yes, normal procedures were 98kts IAS downwind, 94 kts base , and 76 when established on finals

[Chris Trott]

89 knots sounds like the Malibu, but I don't have it, so I'm guessing as much as you.

[Nigel H-J]

Hi Chris, cstorey

This is the Carenado I have.
http://www.flightsimstore.com/product_i ... ts_id=1019


Also just had a quick browse for the pilot notes of this a/c and given below is the the final approach sequence given for the Carenado taken from a PDF File from Langley Flying School.

Descent
Action SOP Call
Obtain ATIS
Conduct clearing turns
Start descent
Maintain the following proximity speeds:
Within 3nm of aerodrome ...................120 MPH
Downwind Leg.................. 115 MPH & 10° Flaps
Base Leg ........................... 110 MPH & 25° Flaps
Final Approach.................... 90 MPH & 40° Flaps
Prior to descent below 1000’ AAE, call for PRELANDING
CHECKLIST
Seat backs......................................................Erect
Seat belts.................................................... Secure
Fuel Selectors....................................................On
Landing Light.....................................................On
Fuel Pumps .......................................................On
Auto Pilot..........................................................Off
Brakes...................................................... Checked
Approach.................................................Briefed14 Wind Conditions .........................Anticipated/ATIS
Vref ............................................................ 90 MPH
Flap Configuration .................................... Flaps 40
Call PRE-LANDING CHECKLIST COMPLETE

Even in the simulator the flying notes for this a/c is an approach speed of 89kts.....so surely this must be correct?

Be Wednesday before I get back here chaps so be patient for any reply.

Regards
Nigel.

[petermcleland]

Whoa Nigel...You have suddenly gone to MPH while all previous were Knots!