Question for Lear 45 pilots
Thread Starter
Join Date: Feb 2002
Location: N20,W99
Age: 53
Posts: 1,119
Likes: 0
Received 0 Likes
on
0 Posts
Question for Lear 45 pilots
Is there a procedure in the FM that deals with asymmetric spoiler activation or retraction?
Do you think that the aircraft would be controllable in the range of 250 KTAS with assymetric spoiler activation?
I haven't flown the Learjet 45 but on the jets I have flown the Spoliers didn't help too much to slow down the aircraft, they were mostly used for increasing descent rate trying to avoid too much airspeed increase, how effective do you consider the Learjet 45's spoilers?
Thank you very much in advance . . . .
Do you think that the aircraft would be controllable in the range of 250 KTAS with assymetric spoiler activation?
I haven't flown the Learjet 45 but on the jets I have flown the Spoliers didn't help too much to slow down the aircraft, they were mostly used for increasing descent rate trying to avoid too much airspeed increase, how effective do you consider the Learjet 45's spoilers?
Thank you very much in advance . . . .
Join Date: Jun 2005
Location: AEP
Age: 80
Posts: 1,420
Likes: 0
Received 0 Likes
on
0 Posts
Lear spoilers
If the new Lear 45s are same as the old ones (flew the 20-30-55 series), spoilers are effective.
But these airplanes have a spoiler EXT/RET switch. Rather stupid.
It is "everything" (45º deployment) or nothing.
Would be so nice to have a handle to meter the amount of drag or lift loss.
xxx
In a classic (old) Lear, deploying the spoilers require 1 second trim NOSE UP to compensate.
Opposite for retraction. Operate trim NOSE DOWN 1 second for retraction.
Curious to see some answers about the 45 and the 60...
Thanks a bunch -
xxx
Happy contrails
But these airplanes have a spoiler EXT/RET switch. Rather stupid.
It is "everything" (45º deployment) or nothing.
Would be so nice to have a handle to meter the amount of drag or lift loss.
xxx
In a classic (old) Lear, deploying the spoilers require 1 second trim NOSE UP to compensate.
Opposite for retraction. Operate trim NOSE DOWN 1 second for retraction.
Curious to see some answers about the 45 and the 60...
Thanks a bunch -
xxx
Happy contrails
Join Date: Jun 2008
Location: Nouvion
Posts: 42
Likes: 0
Received 0 Likes
on
0 Posts
The Lear 45 is not like the the classic Learjets of old , which are all variations of the same theme . The 45 is a clean sheet design , quite a sophisticated little jet for its size with steering , braking and spoileron by wire , though primary controls are still conventional cable . Spoilers can deploy to a maximum of 60 degrees depending on amongst other things , control wheel position , airspeed and flap position . They can act as speed brakes , lift dumps on landing and give roll control augmentation, they also provide the left hand seat with primary roll control during an aileron jam/disconnect situation . The spoilers are hydraulically powered(3000psi) and electronically controlled by RVDT's and a dedicated spoileron computer . In speed brake mode , the spoilers can be deployed to any position desired within the spoiler speed schedule , not just either up or down , as to how effective they are you will have to ask a pilot !
As for asymmetric deployment.....never say never but I think it is highly unlikely . The spoileron computer constantly monitors the whole system , any failure will cause hydraulic power to be removed via a SOV and the hydraulic return to be opened allowing the spoilers to 'blow down' . If the monitor system itself fails to do this , crew can use the control wheel Master Switch to achieve the same effect . In the event of a jam , the computer will command the jammed spoiler to retract for 5 to 7 seconds , the unjammed spoiler remains fully effective . If the jam will not clear
, the AFM procedure is to match the unjammed panel to the jammed panel using the spoiler lever and the EICAS display of panel deployment angle . The AFM also gives a procedure for landing with one or both spoilers deployed , so it would seem that the aircraft is controllable with a jammed panel 
!
Ok I have to rest now , hope this is of some help
As for asymmetric deployment.....never say never but I think it is highly unlikely . The spoileron computer constantly monitors the whole system , any failure will cause hydraulic power to be removed via a SOV and the hydraulic return to be opened allowing the spoilers to 'blow down' . If the monitor system itself fails to do this , crew can use the control wheel Master Switch to achieve the same effect . In the event of a jam , the computer will command the jammed spoiler to retract for 5 to 7 seconds , the unjammed spoiler remains fully effective . If the jam will not clear
, the AFM procedure is to match the unjammed panel to the jammed panel using the spoiler lever and the EICAS display of panel deployment angle . The AFM also gives a procedure for landing with one or both spoilers deployed , so it would seem that the aircraft is controllable with a jammed panel !Ok I have to rest now , hope this is of some help
I seem to remember that assymetric spoiler deployment was one of the exercises we did on the TR course at FS. Part of the training and can be quite interesting as the chance of recovery is low.
MM
MM
Join Date: Mar 2007
Location: toronto
Posts: 427
Likes: 0
Received 0 Likes
on
0 Posts
Lear 45
With the Lear 45, can you deploy the spoilers, and then lower flaps fully?
If it is not allowed, is it possible to deploy the spoilers, forget their deployed, and then deploy full flaps?
If it is not allowed, is it possible to deploy the spoilers, forget their deployed, and then deploy full flaps?
Join Date: Jun 2008
Location: Nouvion
Posts: 42
Likes: 0
Received 0 Likes
on
0 Posts
Robbo , yes you can but spoilers should not be extended at the same time flaps are extended while in flight , except as specified in the EMERGENCY and/or ABNORMAL procedures section of the AFM . With flaps extended any more than 3 degrees , any amount spoiler extension will ping up an amber 'SPOILERS EXT' message on the CAS !
VK
VK
Join Date: Nov 2008
Location: Cleveland, Ohio
Posts: 6
Likes: 0
Received 0 Likes
on
0 Posts
Check my other thread....
Check my other reply on the Lear Mexico City Crash thread for my explaination about LR-45 Flap/Spoilers. Yes, if you ask Bombardier, they will advise you that assymmetic spoiler retraction is "not probable", especially after a service bulletin of a couple of years ago, BUT ask any Flight Safety LR-45 instructor, and thy will tell you that there have been a least 3 reported cases of it actually happening. In fact, they will run the scenareo in the sim for you, as they did for me. Very aerobatic! As such, SOP's for the spoiler application and retraction is "slow and deliberate". This is a rather early serial 45 (#028), maybe it didn't get mod'ed, coupled with a fast hand on the spoilers as they hurried to 'go down/slow down'.......
Join Date: Jun 2008
Location: Nouvion
Posts: 42
Likes: 0
Received 0 Likes
on
0 Posts
Yes falcon , you are correct . IIRC the SB was to replace the hydraulic flexible hoses to the actuators with new ones that incorporated an inline filter . Less than clean hydraulic fluid was causing problems withn the actautors and this was Bombardiers fix .
VK
VK
Join Date: Nov 2008
Location: Cleveland, Ohio
Posts: 6
Likes: 0
Received 0 Likes
on
0 Posts
Von Kinkerhoffen...
...you are a very knowledgeable Lear 45 resource. I could not remember the specific's of that SB, nor do I remember if it was mandatory. I know that the issue applied to early serial aircraft, and I would suspect that this SB would be required. However, that doesn't necessarily mean that it was actually completed on a, dare I say, non US/Canadian/EU registered aircraft!
Join Date: May 2006
Location: On the right of the clowns and to the left of the jokers
Posts: 307
Likes: 0
Received 0 Likes
on
0 Posts
Asymmetric Spoiler Deployment
In the sim it resulted in a VERY high roll rate and required the controls hard against the roll to bring it under control (I don't recall weather the roll could actually be stopped with max differential spoileron)
It's some years since I've flown the type and I cant recall if there was a spoileron SB at the time.
It's some years since I've flown the type and I cant recall if there was a spoileron SB at the time.
Join Date: Nov 2008
Location: Champaign, IL
Posts: 1
Likes: 0
Received 0 Likes
on
0 Posts
Just went through recurrent in ATL a couple months ago for the 45. Like was previously said, there are 3 reports of asymmetrical spoiler deployments. If my memory serves me right at least 1, maybe 2 were on FedEx airplanes on approach to landing. (Fedex was the launch customer for the LR45). So there is a SB now because of those early bugs. Atlanta Flightsafety is showing asymmetrical deployments at 3 speeds all in clean config: about 200, 250 and 310 indicated. 200 is manageable with opposite aileron, 250 you need to pull the spoilers hoping the opposite side comes out, and at 310, unless you know it's coming you are probably going to roll. Like was mentioned earlier, spoilers are not to be used with flaps. Hope this helps.
Join Date: Aug 2007
Location: Vancouver, Canada
Posts: 60
Likes: 0
Received 0 Likes
on
0 Posts
falcon50flyer,
You write, "Yes, if you ask Bombardier, they will advise you that assymmetic spoiler retraction is "not probable", especially after a service bulletin of a couple of years ago, BUT ask any Flight Safety LR-45 instructor, and thy will tell you that there have been a least 3 reported cases of it actually happening."
What I really want to know from Flight Safety is how many incidents have there been after the SB. Often we get so caught up in telling 'war stories' from the past that we forget the problem has been fixed and is unlikely to re-occur and thus our training and understanding of the aircraft we fly is compromised.
best regards,
Bruce Waddington
You write, "Yes, if you ask Bombardier, they will advise you that assymmetic spoiler retraction is "not probable", especially after a service bulletin of a couple of years ago, BUT ask any Flight Safety LR-45 instructor, and thy will tell you that there have been a least 3 reported cases of it actually happening."
What I really want to know from Flight Safety is how many incidents have there been after the SB. Often we get so caught up in telling 'war stories' from the past that we forget the problem has been fixed and is unlikely to re-occur and thus our training and understanding of the aircraft we fly is compromised.
best regards,
Bruce Waddington
Bruce,
I have not been to FS Atlanta for many years, but as you alude to along time ago there did seem to be a difference of opinion about what to emphasis betwen FS Atlanta and Bombardier Dallas.
You can easily find all the LR45 incidents by searching the FAA NTSB - Aviationand CAA Air Accidents Investigation: Homeincident databases. You would alos have to repeat this for all the different authorities Air Accidents Investigation: Worldwide links
Alternatively you could write a polite letter to Bombardier tech support to ask for the information so you can improve training and dispell any myths.
MM
I have not been to FS Atlanta for many years, but as you alude to along time ago there did seem to be a difference of opinion about what to emphasis betwen FS Atlanta and Bombardier Dallas.
You can easily find all the LR45 incidents by searching the FAA NTSB - Aviationand CAA Air Accidents Investigation: Homeincident databases. You would alos have to repeat this for all the different authorities Air Accidents Investigation: Worldwide links
Alternatively you could write a polite letter to Bombardier tech support to ask for the information so you can improve training and dispell any myths.
MM
Join Date: Nov 2008
Location: Cleveland, Ohio
Posts: 6
Likes: 0
Received 0 Likes
on
0 Posts
Lear 45 Spoiler SB
Bruce-
I took my initial LR-45 training/type rating at FSI Atlanta in June of this year. We discussed the spoiler retraction issue at some length before and after one of the simulator sessions and we did a demonstration of an asymmetric retraction in the sim. We set up the condition to include a fairly normal decent, about 280KIAS and power to idle with full spoiler deflection. At the point of retaction, the sim. instructor failed one wing spoiler to remain extended while the other retacted. The roll rate is pnenominal!
The procedure that FSI Atlanta teaches is to move the spoiler handle slowly and remain vigilant during any spoiler movement to an uncommanded roll action. If the aircraft rolls, you should move the spoiler handle as neccesary to stop the rolling tendancy (i.e. match the wings spoilers in extension angle) and then recover the aircraft. If you are not fully prepared for this situation, the aircraft may have rotated 2-3 times before you know it and it is very easy to lose pitch control of the aircraft at the same time. The result is a complete upset and overspeed. Definately not good at a relatively low altitude! FSI Atlanta told me that they knew of at least three such occurences, but the crews were able to recover.
As I understand it, FSI in Atlanta and Tucson continue to train for this possibility on the LR-45 because they believe that it is still a possibility, service bulletin or not. Bombardier Dallas does not. While not stated explicitly, the instructors at FSI left me with the impression that they felt Bombardier was not teaching it for "legal reasons", i.e., don't teach a situation that we might then be forced to admit could still happen. As far as Bombardier is concerned, the situation has been rectified. FSI, on the other hand, is not so sure.
I was told by the FSI instructors that there have been no such occasions (that they know of) since this service bulletin was issued. However, I do not recall whether they stated if the SB was manditory or not. (seems like it should be). Nor do we know if this SB was incorporated on this early serial number 45 ( 028). If you know much about the Lear 45, then you know that the number of bulletin's issued on that aircraft have been quite numerous.
I presented this possible scenario not in an effort to besmirch Bombardier or the Lear 45, but rather instead because it fits into the realm of possible explainations, given what information we have. All suggestions as to the potential cause on forums such as this are understood to be merely "armchair speculation" at this point, and will remain only as much until a full investigation is conducted. I'm sure that a few will look upon the outcome of even an official investigation with some suspicion, given the political position of some of the victims.
In the meantime, for those who do wish to speculate, postulations will be fomulated given what is known and what can be deduced given previous experiences. A Lear 45 experiences an upset and loss of control during an approach immediately following a high speed decent and while in trail of a large airliner. A passenger is a high-ranking goverment official instrumental in fighting against ruthless drug-lords. The cause? Unknown as of yet. Speculation? Plenty of room for that.
I took my initial LR-45 training/type rating at FSI Atlanta in June of this year. We discussed the spoiler retraction issue at some length before and after one of the simulator sessions and we did a demonstration of an asymmetric retraction in the sim. We set up the condition to include a fairly normal decent, about 280KIAS and power to idle with full spoiler deflection. At the point of retaction, the sim. instructor failed one wing spoiler to remain extended while the other retacted. The roll rate is pnenominal!
The procedure that FSI Atlanta teaches is to move the spoiler handle slowly and remain vigilant during any spoiler movement to an uncommanded roll action. If the aircraft rolls, you should move the spoiler handle as neccesary to stop the rolling tendancy (i.e. match the wings spoilers in extension angle) and then recover the aircraft. If you are not fully prepared for this situation, the aircraft may have rotated 2-3 times before you know it and it is very easy to lose pitch control of the aircraft at the same time. The result is a complete upset and overspeed. Definately not good at a relatively low altitude! FSI Atlanta told me that they knew of at least three such occurences, but the crews were able to recover.
As I understand it, FSI in Atlanta and Tucson continue to train for this possibility on the LR-45 because they believe that it is still a possibility, service bulletin or not. Bombardier Dallas does not. While not stated explicitly, the instructors at FSI left me with the impression that they felt Bombardier was not teaching it for "legal reasons", i.e., don't teach a situation that we might then be forced to admit could still happen. As far as Bombardier is concerned, the situation has been rectified. FSI, on the other hand, is not so sure.
I was told by the FSI instructors that there have been no such occasions (that they know of) since this service bulletin was issued. However, I do not recall whether they stated if the SB was manditory or not. (seems like it should be). Nor do we know if this SB was incorporated on this early serial number 45 ( 028). If you know much about the Lear 45, then you know that the number of bulletin's issued on that aircraft have been quite numerous.
I presented this possible scenario not in an effort to besmirch Bombardier or the Lear 45, but rather instead because it fits into the realm of possible explainations, given what information we have. All suggestions as to the potential cause on forums such as this are understood to be merely "armchair speculation" at this point, and will remain only as much until a full investigation is conducted. I'm sure that a few will look upon the outcome of even an official investigation with some suspicion, given the political position of some of the victims.
In the meantime, for those who do wish to speculate, postulations will be fomulated given what is known and what can be deduced given previous experiences. A Lear 45 experiences an upset and loss of control during an approach immediately following a high speed decent and while in trail of a large airliner. A passenger is a high-ranking goverment official instrumental in fighting against ruthless drug-lords. The cause? Unknown as of yet. Speculation? Plenty of room for that.
Last edited by falcon50flyer; 13th Nov 2008 at 21:39.
Join Date: Aug 2007
Location: Vancouver, Canada
Posts: 60
Likes: 0
Received 0 Likes
on
0 Posts
Hi falcon50flyer,
Thanks for the additional information.
I finished training on the Lear 45 around the end of June 2008 (Flight Safety Tucson and our own company Line Training) and now have about 140 hours on the machine. I do not recall doing the spoiler extended scenario in our Simulator training but it was discussed during company line training.
It surprises me that if this scenario occurs the recovery procedure is via an Abnormal Checklist instead of a Recall Drill but based on what I have been reading it seems that lots of rudder and aileron will be needed as you try and get the speedbrakes into a symetrical position and then apply the appropriate checklist.
Thanks again for your input.
best regards,
Bruce Waddington
Thanks for the additional information.
I finished training on the Lear 45 around the end of June 2008 (Flight Safety Tucson and our own company Line Training) and now have about 140 hours on the machine. I do not recall doing the spoiler extended scenario in our Simulator training but it was discussed during company line training.
It surprises me that if this scenario occurs the recovery procedure is via an Abnormal Checklist instead of a Recall Drill but based on what I have been reading it seems that lots of rudder and aileron will be needed as you try and get the speedbrakes into a symetrical position and then apply the appropriate checklist.
Thanks again for your input.
best regards,
Bruce Waddington
