FPV 737 usefulness
 

Having a bit of an argument with my housemate on the overall usefulness of the FPV in the 737. I think it's useful enough to use it as extra reference but he is embarrassed by me saying that hahahaha your thoughts?

I find it completely useless, especially when there is a crosswind.

I just switch it on for fun to confirm my mental maths. I never use it as a reference.

Yep,useless in normal ops,never using it even when flying raw data.

Guess one has to have fighter backround to really appreciate it maybe .... good for steep turns though :)

FPV is very, very usefull when encountering unusual attitudes. You can put the FPV on the horizon and the airplane will fly level.

The optimum difference between the FPV and airplane attitude is 5 degrees. If it is more, you need to select flaps.

Also useful for flying raw data ILS - as you approach the GS you want the FPV to be 3 degrees or so below horizon

At KAL, they used the FPV for base and turn to final on a visual approach.

I used the display above the glareshield, myself.

"FPV is very, very usefull when encountering unusual attitudes. You can put the FPV on the horizon and the airplane will fly level.

The optimum difference between the FPV and airplane attitude is 5 degrees. If it is more, you need to select flaps."



I just commented on the 737-800 high altitude stall recovery thread. This post is an example of techniques that work in some events but won't work in all events. If you experience a very high AOA event putting the FPV on the horizon WON'T NECESSARILY reduce the AOA below the stall AOA or perhaps won't allow the aircraft to fly level.

"The optimum difference"? You need to select flaps prior to the minimum flap speed. There is no "optimum difference".

I have about 2500 hrs with Boeing AOA gauges. Using the FPV differential is less accurate than using the AOA but we still used the minimum flap speeds which is Boeing's procedure.

What I find very disturbing is guys who have had no advice, but like toys; switch on FPV & FD. SOP is to have FD on at all times. Here is an FPV with no SOP advice. They have both on?????????
I then hear of guys who advocate using FPV for the final of a circling approach. This is a visual approach from low level. You are looking out of the window having set an attitude. IMHO the minuscule FPV is the last thing you should be looking at.

"The optimum difference between the FPV and airplane attitude is 5 degrees. If it is more, you need to select flaps."

Now I know what was wrong with my NG over 10 years of operating. And there was me tolerating 2.5/3.0 degress NU attitude in level cruising flight!

Funny the F/O never ever suggested I lower flap to correct this wierd anomaly, maybe they were afraid of upsetting a grumpy old fart??!!

Newbies, please be wary of what you read in these pages. Whomsoever came up with this rubbish should try getting some real experience before pontificating on the topic of attitude flying.

I thought this was the "Professional"/"Flight Deck" forum??!! :rolleyes:

Barkingmad, relax. This hasn't been a "professional forum" for some time...

The FPV is handy on NP approaches with a variable crosswind as it reacts more quickly than the eye can detect drift - particularly at night. If the approach is not stabilized however, it is next to useless. Other than that and as mentioned, a wind shear warning, the FPV should serve as a cross-check item only and one should never focus on the thing.

The FPV is more useful on a HUD than on a PFD, but it is still useful. I don't know if I would feel that way, however, if I hadn't gotten used to it first by flying with a HUD as the primary instrument.

The absolutely best use for the FPV is in the case of unreliable airspeed. You can simply fly AOA using the FPV.

The FPV is where the aircraft is going, instantaneously. The perpendicular distance, in degrees, from where the aircraft is pointed, and the FPV, is you AOA.

Cruise is 2-3 degrees. Clean maneuvering or any maneuvering flap speed is around 7. I believe approach is flown at 4-5. Stall on a 737 is low teens, I can't remember the exact figure.

Boeing doesn't use the FPV in it's loss of airspeed checklist because they don't know under which situations it will, or won't, be displayed.

It isn't a primary instrument. If other instruments, and Boeing's procedures, are working and the FPV is displayed and working it can be used. The problem is many people tried to make it a primary instrument which gets into the inappropriate techniques post I made previously.

FPV
 

Although it can be useful i almost never use it.

Dont use it in Airspeed Unreliable. It will show on the display but pitot/static information is fed into it somehow so it cant be garanteed to show correctly!

The times i would use it are on a (night) NPA in gusty conditions, after you switch off the F/D's the FPV symbol doubles in size. You can determine your vertical path (relative to the horizon) as well as drift (the FPV symbol below the vertical bar is 10 deg, end of the horizontal bar is 20 deg). The FPV is very sensitive therefor it helps in detecting windshear.

Most pilots I fly with dislike it. Same goes for VSD but thats a different topic.

Having flown the HUD (in which flight path vector is the primary focus in most phases of flight), I find it handy (when I don't have a HUD) for:

1. Engine out acceleration;

2. Raw data (i.e. no flight director) hand flying, such as visual circuits (both for maintaining level flight and subsequently establishing 3 degree approach, or steep turns, or various other raw data manoeuvres.

I find it more useful in simulators than the aircraft, mainly because the above manoeuvres are generally done in simulators rather than the aircraft, and there is less "feedback" and/or "feel" in a simulator than in a real aircraft, so the more aids the better. But having practiced using it in those scenarios in simulators, if I ever found myself in one of those situations in an aircraft on a dark and stormy night, I would probably use it. Hence I always have it turned on.

You can, of course, achieve everything just as easily by scanning to the IVSI, the only difference being that the FPV is closer to the centre of the ADI so can be monitored more closely (or even continuously) while flying attitude as the primary instrument.

I once believed it may be useful in an unreliable airspeed scenario, but Boeing have since updated the checklist to say it may not be reliable (as noted by previous poster). I actually really like that advice, because attitude and thrust really should be the only things you are thinking about in an unreliable airspeed scenario.

Dismissing it as a toy is a bit rich. It is not intended to replace a flight director, but in the event you don't have a flight director it becomes more useful. In fact, in a HUD, it is generally used in conjunction with a guidance cue, which is simply a flight director referenced to the flight path vector rather than the aircraft nose.

The FPV is much more cleverly designed and can be much more effectively used then what most people think. The designers of it have put a lot of thought and expertise in the functionality and it should be treated as such, not put down as an ineffective tool. More in-depth knowledge of the tool would be more beneficial to pilots, unfortunately that knowledge is not readily available as many "trainers" are not aware of its full capacity.

The tool is introduced on NG and future fleets and thus is here to stay, learn from it, look into its design more detailed and see what clever functionality it offers and when it is removed from view (when not able in providing accurate enough information to you) and then post back on the "useless", "never use it", tool called FPV

Interesting discussion. I currently fly the Airbus and find the FPV very useful to aid accurate manual flight.

I'll be on the 737 Max in a few years and am glad to hear that the feature will still be available.

Pity there won't be a table to eat off :(

Having flown both types the FPV has more uses on the A320 etc as the a/c (under normal law) is trajectory stable. Also on the Airbus there is a scale on the horizon on the Attitude Indicator and the desired track can be set showing as an index - these facilities are not available on the B737 NG but maybe the Max will be different?