In re Crash of Aircraft N93PC on July 7, 2013, at Soldotna, Alaska

WO IN THE UNITED STATES DISTRICT COURT
FOR THE DISTRICT OF ALASKA
In re Crash of Aircraft N93PC ) No. 3:15-cv-0112-HRH
) [Consolidated with
on July 7, 2013, at Soldotna, Alaska ) No. 3:15-cv-0113-HRH and
_______________________________________) No. 3:15-cv-0115-HRH]
O R D E R
Motions in Limine to Exclude Testimony of John Cochran
Defendants Texas Turbine Conversions, Inc. and Recon Air Corporation move to
exclude certain testimony of plaintiffs’ expert, Dr. John Cochran.1 These motions are
opposed.2 The request for oral argument on these motions has been withdrawn,3 and the
court deems oral argument unnecessary.
Background
On July 7, 2013, a deHavilland DHC-3 “Otter” airplane operated by Rediske Air, Inc.
and piloted by Walter Rediske crashed shortly after take-off from the Soldotna Airport.
Rediske and all of the passengers on board were killed in the crash. Plaintiffs, which are the
1Docket Nos. 268 and 311.
2Docket Nos. 294, 296, 337, and 338.
3Docket No. 358.
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estates of the passengers and Rediske, assert wrongful death, negligence, strict liability and
breach of warranty claims against defendants.
The subject aircraft was modified in 2010. As part of that modification, Recon Air
installed a Texas Turbine conversion kit which converts a standard piston engine to a turbine
engine. Texas Turbine provides the conversion kit pursuant to an FAA approved
supplemental type certificate, STC #SA09866C. The conversion kit contains the parts
necessary to mount a turbine engine in the aircraft. More specifically, the “conversion kit
includes a new propellor, engine mount, starter/generator, instruments, engine cowlings,
batteries, oil cooler, generator control unit, steel enclosures for batteries and electrical relays,
bleed-air ejector vacuum system, bleed-air heater system, and other miscellaneous
components.”4 The turbine engine that was installed in the subject aircraft was manufactured
by Honeywell. As part of the 2010 modification, Recon Air also installed a Baron Short
Takeoff & Landing (STOL) kit. The STOL kit was provided by Stolairus Aviation, Inc.
Plaintiffs contend that their negligence claim against Texas Turbine is based on
allegations that Texas Turbine “was negligent in failing to determine that the addition of its
Texas Turbine Conversion kit to a DHC-3 aircraft[] effected the aircraft’s neutral point,
which contributed to the aircraft being unstable in pitch[.]”5 Plaintiffs contend that their
4Texas Turbine Conversions, Inc.’s Motion for Summary Judgment at 3, n.8, Docket
No. 267.
5Plaintiffs’ Responses to Texas Turbine’s Motion in Limine to Exclude the Testimony
of Dr. John Cochran at 1, Docket No. 294.
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strict liability claim against Texas Turbine is based on the fact that Texas Turbine was “the
seller of the Honeywell engine that failed in flight.”6 Plaintiffs’ claims against Recon Air are
based on allegations that as an installer, it had a responsibility to ensure that all of the
modifications were compatible and
in particular, failed to detect that the incorporation of the Texas
Turbine Conversion and the “STOL Kit” into the accident
aircraft had changed a critical relationship between the aircraft’s
“center of lift” (CL)[7] and “center of gravity” (CG),[8] and this
change in relationship caused the accident aircraft to be uncon-
trollable in the longitudinal axis (nose up and down) axis, which
resulted in a stall and fatal crash after an in-flight engine
failure.[9]
Plaintiffs retained Dr. John Cochran as an expert to provide “opinions as to the cause,
or causes, of the accident.”10 Dr. Cochran is a professor of aerospace engineering, whose
6Id.
7The “center of lift” is “[t]he location along the chord line of an airfoil at which all of
the lift forces produced by the airfoil are considered to be concentrated.” FAA Weight and
Balance Handbook, Exhibit A at 3, Plaintiff’s [sic] Responses to Recon Air Corporation’s
Motion in Limine to Exclude the Testimony of Dr. John Cochran, Docket No. 337.
8The “center of gravity” or “CG” is “[t]he point at which an airplane would balance
if suspended.” Id.
9Plaintiff’s [sic] Responses to Recon Air Corporation’s Motion in Limine to Exclude
the Testimony of Dr. John Cochran at 2, Docket No. 337.
10Expert Report of John E. Cochran, Jr., Exhibit A at 4, Memorandum in Support of
RAC’s Motion in Limine No. 2 (Cochran), Docket No. 312.
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“academic specializations include dynamics, guidance, stability, and control of airplanes,
helicopters, missiles, and launch vehicles.”11 Dr. Cochran has offered three opinions:
Opinion 1. The accident aircraft . . . crashed because it was
unstable in pitch. The pitch instability was due to the changes
in the neutral point location[12] caused by the installed Stolairus
STOL kit, the Texas Turbine conversion, i.e., turbine engine,
propeller, and modifications of the aircraft’s nose.
* * *
Opinion 2. Texas Turbine, Inc. should have determined the
effects of its conversion on the neutral point location in con-
verted DHC-3 aircraft.
* * *
Opinion 3. Both Stolairus Aviation, Inc. and Texas Turbine,
Inc. should have conducted flight tests to determine the effects
of their STCs on the neutral point location in a DHC-3
aircraft.[13]
Dr. Cochran relied on the NTSB’s Video Study and Soldotna Kinematics Study in
formulating his opinions, in particular his Opinion 1. One of the passengers on the accident
aircraft made a cell phone video, and the NTSB’s investigators “analyzed the video and
produced an estimated trajectory of the aircraft (altitude vs. time) and estimates of its pitch
11Id. at 3.
12The “neutral point location” is the same as the “center of lift.”
13Expert Report of John E. Cochran, Jr., Exhibit A at 14-15, Memorandum in Support
of RAC’s Motion in Limine No. 2 (Cochran), Docket No. 312.
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angle and ground speed.”14 The NTSB then used the Video Study to generate a report
entitled the Soldotna Kinematics Study, in which the NTSB estimated the accident aircraft’s
weight and the center of gravity location at the time of the accident. Using the NTSB data,
Dr. Cochran did his own mathematical calculations and based on those calculations
concluded that at 11.25 seconds after the accident aircraft left the runway, “[t]he large values
of angle of attack and decreasing speed indicate that a stall is imminent. The rate of increase
indicates that the aircraft is unstable in pitch.”15
Texas Turbine and Recon Air (referred to collectively as “defendants” herein) now
move to exclude Dr. Cochran’s opinions and testimony.
Discussion
Rule 702 of the Federal Rules of Evidence provides that expert
opinion evidence is admissible if: (1) the witness is sufficiently
qualified as an expert by knowledge, skill, experience, training,
or education; (2) the scientific, technical, or other specialized
knowledge will help the trier of fact to understand the evidence
or to determine a fact in issue; (3) the testimony is based on
sufficient facts or data; (4) the testimony is the product of
reliable principles and methods; and (5) the expert has reliably
applied the relevant principles and methods to the facts of the
case.
City of Pomona v. SQM North America Corp., 750 F.3d 1036, 1043 (9th Cir. 2014). “Before
admitting expert testimony into evidence, the district court must perform a ‘gatekeeping role’
of ensuring that the testimony is both ‘relevant’ and ‘reliable’ under Rule 702.” United
14Id. at 5.
15Id. at 8.
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States v. Ruvalcaba-Garcia, 923 F.3d 1183, 1188 (9th Cir. 2019) (quoting Daubert v. Merrell
Dow Pharmaceuticals, Inc., 509 U.S. 579, 597 (1993)).
“Relevancy simply requires that ‘the evidence logically advance a material aspect of
the party’s case.’” Id. (quoting Estate of Barabin v. AstenJohnson, Inc., 740 F.3d 457, 463
(9th Cir. 2014)). “Expert testimony which does not relate to any issue in the case is not
relevant and, ergo, non-helpful.” Daubert, 509 U.S. at 591 (citation omitted).
“‘[R]eliability’ . . . requires that the expert’s testimony have ‘a reliable basis in the
knowledge and experience of the relevant discipline.’” Ruvalcaba-Garcia, 923 F.3d at 1188-
89 (quoting Barabin, 740 F.3d at 463). “The district court must assess whether ‘the
reasoning or methodology underlying the testimony is scientifically valid’ and ‘properly can
be applied to the facts in issue[.]’” Id. at 1189 (quoting Daubert, 509 U.S. at 592–93). “‘The
district court is not tasked with deciding whether the expert is right or wrong, just whether
his testimony has substance such that it would be helpful to a jury.’” City of Pomona, 750
F.3d at 1044 (quoting Alaska Rent-A-Car, Inc. v. Avis Budget Group, Inc., 738 F.3d 960,
969-70 (9th Cir. 2013)). “The court must assess the expert’s reasoning or methodology,
using as appropriate criteria such as testability, publication in peer-reviewed literature,
known or potential error rate, and general acceptance.” Id. “‘But these factors are meant to
be helpful, not definitive, and the trial court has discretion to decide how to test an expert’s
reliability as well as whether the testimony is reliable, based on the particular circumstances
of the particular case.’” Id. (quoting Primiano v. Cook, 598 F.3d 558, 564 (9th Cir. 2010)).
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As an initial matter, plaintiffs contend that defendants have misstated Dr. Cochran’s
first opinion. Defendants contend that Dr. Cochran opined that the modifications moved the
aft center of gravity limit forward by 3.12 inches. Plaintiffs, however, contend that “Dr.
Cochran’s opinion is” that the modifications “moved the neutral point of a DHC-3 Otter 3.12
inches forward.”16 In other words, plaintiffs seem to be contending that defendants think Dr.
Cochran was opining about the center of gravity when he was actually opining about the
neutral point.
Defendants argue that the distinction between the neutral point and the center of
gravity is irrelevant to what is at issue in the instant motions. Defendants contend that the
primary issue here is whether Dr. Cochran’s opinions are reliable in light of the fact that he
has admitted that flight testing is the only way to confirm his mathematical hypothesis. Dr.
Cochran’s opinions are based on his use of aerodynamic mathematical principles, but
defendants argue that mathematical models are not the most reliable means to predict real-
world flight characteristics, as Dr. Cochran acknowledged. In his report, Dr. Cochran stated
that “the best way to determine the effects of power on the stability characteristics of a
single-engine, propeller driven aircraft is through flight tests of the aircraft.”17 And in
support of his Opinion 3, Dr. Cochran stated that “[f]light tests are the best, and often the
16Plaintiffs’ Responses to Texas Turbine’s Motion in Limine to Exclude the
Testimony of Dr. John Cochran at 7, Docket No. 294.
17Expert Report of John E. Cochran, Jr. at 10, Exhibit A, Memorandum in Support of
RAC’s Motion in Limine No. 2 (Cochran), Docket No. 312.
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only, way to determine effects of nonlinear aerodynamics.”18 But what Dr. Cochran was
unaware of when he wrote his report, according to defendants, is that Texas Turbine had
conducted flight testing in 2000. Defendants contend that this 2000 flight testing was
conducted under FAA supervision and included “test of the flight and handling characteris-
tics of the airplane beyond maximum gross weight, up to and beyond the existing aft CG
limits published in the Airplane Flight Manual for the DHC-3.”19 At his deposition, Dr.
Cochran testified that since he wrote his expert report, he learned that Texas Turbine had
conducted the 2000 flight testing and that he
had no reason to question the accuracy of the data. It appeared
to be -- the flight tests, multiple ones, appeared to be done in the
proper manner with FAA representation and Texas Turbine
pilots and so forth. And so as far as it goes, I would say that . . .
there was no question about the test.[20]
Dr. Cochran further testified that “I can’t fault Texas Turbine for doing what the FAA said
they needed to do to get the aft CG” and “I can say that Texas Turbine apparently did what
was required of them as far the FAA is concerned.”21 Thus, defendants contend that Dr.
Cochran’s second opinion (that Texas Turbine should have determined the effects of its
18Id. at 15.
19Texas Turbine Conversions, Inc.’s Motion for Summary Judgment at 2, Docket No.
267.
20Deposition of John E. Cochran at 29:16-22, Exhibit B, Texas Turbine Conversions,
Inc.’s Motion to Exclude Testimony of Plaintiffs’ Expert John Cochran, Exhibit B, Docket
No. 268.
21Id. at 123:15-16; 124:7-9.
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conversion on the neutral point) is not just unreliable, but wrong, which in turn, renders his
first opinion unreliable (that the change in neutral point caused the pitch instability).
As plaintiffs point out, Dr. Cochran raised some questions about the 2000 flight tests.
At Dr. Cochran’s deposition, the following exchange took place:
Q Do you agree that in those flight tests the aircraft handled
acceptably in all flight regimes?
A Most of them.
Q In which flight regime did the flight test not show that the
aircraft handled acceptably?
A There’s some question about what happens when . . . they
were testing the aircraft at aft CG and gross weight actually a
little bit over 8,000 pounds with . . . landing flaps and doing
stalls. Because during that test they got a rolling of the aircraft
and yawing that was not exactly what you would want to have
because the aircraft rolled 30 degrees or more[.] And you would
like for the aircraft to stall in such a way that it just stays wing
level and just pitches down after it stalls in a recovery mode.
Q I may --
A Furthermore -- well, there’s one more, thing, too, that’s
a little bit different here. The -- they indicate in the test that
they’re doing the test at 75 percent torque instead of maybe 100
percent torque which would imply that . . . they’re not conduct-
ing the test at full . . . power.
Q And what implication does that have, in your opinion?
A Power affects the stability of the aircraft, the application
of power. And the application of more power affects the
stability more. So that would -- that would change, change
things.
Q So recognizing that the flight test showed that the aircraft
was operating at 75 percent torque, do you agree that the flight
test as reported by Texas Turbine indicated that the aircraft
handled acceptably?
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A Well, it was accepted. It did not handle as they expected
it, I don’t think.[22]
Dr. Cochran’s testimony does not indicate that Dr. Cochran thought the 2000 flight tests were
sufficient or that they changed his opinion that flight testing should have been done after the
2010 conversion of the accident aircraft was completed.
Moreover, the 2000 testing was not the type of flight testing that Dr. Cochran has
opined defendants failed to do here. Rather, Dr. Cochran testified that Texas Turbine did not
do a flight test of “an aircraft which had both the Texas Turbine conversion and the STOL
kit” and that “a lot of my opinion, total opinion, is based on the fact that in combination, the
addition of the STOL kit plus the change to the turbine engine together caused changes in
the stability of the aircraft.”23 Dr. Cochran explained that it was his opinion that
a test to determine the neutral point location, neutral point
movement, and so forth would be the kind of test that you would
do. And it would require that you fly the aircraft at different
flight conditions and measure the change in . . . the elevator
deflection, the function of lift coefficient and some things like
that, change the CG and make some plots, a plot to determine by
extrapolation the neutral point. That would be one kind of
test.[24]
22Cochran Deposition at 30:2-31:14, Exhibit B, Texas Turbine Conversions, Inc.’s
Motion to Exclude Testimony of Plaintiffs’ Expert John Cochran, Exhibit B, Docket No. 268.
23Id. at 28:22-29:3.
24Id. at 174:23-175:7.
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Dr. Cochran testified that if this type of flight testing had been done, flight testing an aircraft
that contained both the turbine conversion and the STOL kit, it would have helped determine
whether his opinions were correct or not.25
Defendants are quick to point out that Dr. Cochran did not actually do this type of
flight testing. In fact, at his deposition he testified that he “didn’t really push [the need for
flight testing] that much or anything. But, I mean, my conclusion was that you, know, they
should have done the test. But . . . that’s basically where it stopped[.]”26
Nonetheless, plaintiffs argue that Dr. Cochran’s opinions are not unreliable simply
because he did not perform flight testing that he opined should have been done. Plaintiffs
insist that his opinions are reliable because they are based on proven aerodynamic formulas,
formulas that were also used by defense expert, Mark Madden, and by the NTSB
investigators. Plaintiffs insist that Dr. Cochran’s methodology of calculating the movement
of the neutral point on the accident aircraft is based on sound and well-established
aerodynamic formulas and principles. Plaintiffs contend that flight testing is simply another
methodology and that “‘[i]t is not uncommon for opposing experts to reach different
conclusions, using different methodologies. It is for the jury to assess which is the more
reliable and helpful.’” Lewert v. Boiron, Inc., 212 F. Supp. 3d 917, 934 (C.D. Cal. 2016)
(quoting Rocky Mountain PSI, LLC v. Thayer, No. CV 13-23, 2015 WL 1579492, at *3 (D.
25Id. at 176:5-11.
26Id. at 175:19-22.
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Mont. Apr. 9, 2015)). Plaintiffs argue that expert testimony should not be excluded merely
because one expert uses one methodology and one expert uses another methodology, if both
methodologies are accepted and proven in the field. “‘Daubert neither requires nor
empowers trial courts to determine which of several competing scientific theories has the best
provenance.’” Marketquest Group, Inc. v. BIC Corp., Case No. 11-cv-618-BAS (JLB), 2018
WL 1756117, at *4 (S.D. Cal. April 12, 2018 (quoting Ruiz-Troche v. Pepsi Cola, 161 F.3d
77, 85 (1st Cir. 1998)).
Defendants dispute that flight testing is simply a different methodology. Rather,
defendants contend that according to Dr. Cochran himself, it is the superior methodology.
Defendants contend that this is not a case in which the jury will be able to weigh the merits
of two different methodologies as plaintiffs seem to be suggesting but rather is a case in
which plaintiffs’ expert has conceded that flight testing is the superior methodology and the
only way to prove his theories.
But even if flight testing is simply another methodology, defendants argue that Dr.
Cochran’s opinions should still be excluded as unreliable because the very flight testing he
recommended was in fact completed after his deposition. Robert Carducci, a defense expert,
observed this 2018 flight testing and reports that a DHC-3 aircraft modified with the turbine
conversion and the STOL kit, with full flap setting, was controllable with an aft center of
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gravity of 152.2. inches, which was the published limit at the time of the accident.27 In other
words, according to defendants, the flight testing proved the combined installation of the
Texas Turbine conversion and the STOL kit did not affect the controllability of the aircraft.
Thus, defendants argue that Dr. Cochran’s opinions have been demonstrated to be incorrect
by the very means he acknowledged was the best way to test his theories. Given that Dr.
Cochran’s opinions have been refuted by reliable evidence, defendants argue that his
opinions cannot possibly be considered reliable and they should be excluded.
The fact that defendants have now flight tested an aircraft with both the turbine
conversion and the STOL kit installed raises some questions about Dr. Cochran’s opinions,
but it does not render his opinions unreliable. The mathematical methodology he used is
based on well-established aerodynamic formulas and principles, which make his opinions
reliable, as far as they go.
Defendants next argue that Dr. Cochran’s opinions are unreliable because they are
based on insufficient facts or data. Defendants contend that Dr. Cochran stated that in
determining whether the aircraft was unstable in pitch during takeoff, one must accurately
calculate the angle of attack of the accident aircraft and the neutral point. Defendants argue
that Dr. Cochran made critical mathematical errors when he re-calculated the NTSB raw data
from the Kinematics Study. As defense expert Carducci opined, “Dr. Cochran has made
27Carducci Rebuttal Report at 33-34, Exhibit C, Texas Turbine Conversions, Inc.’s
Motion to Exclude Testimony of Plaintiffs’ Expert John Cochran, Docket No. 268.
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significant errors in his calculations for ground speed, flight angle, pitch angle, and angle-of-
attack.”28 In particular, defendants contend that Dr. Cochran incorrectly calculated the pitch
angle values, which were then used to derive the geometric angle of attack. Because his
opinions are based on his mathematically incorrect calculations, defendants argue that Dr.
Cochran’s opinions cannot be considered reliable.
But, “‘the factual basis of an expert opinion goes to the credibility of the testimony,
not the admissibility.’” Hangarter v. Provident Life & Acc. Ins. Co., 373 F.3d 998, 1018
n.14 (9th Cir. 2004) (quoting Children’s Broad. Corp. v. Walt Disney Co., 357 f.3d 860, 865
(8th Cir. 2004)). If Dr. Cochran made mathematical errors, that it something defendants can
cross-examine him about. But it is not necessarily a reason to exclude his expert testimony.
Defendants next argue that Dr. Cochran’s opinions are not reliable because he failed
to consider that the landing flaps were fully extended when the accident aircraft was taking
off. At his deposition, Dr. Cochran testified that having the landing flaps fully extended
would affect the movement of the neutral point,29 but that he did not factor this in because
“I did not have enough information to come up with an estimate for the fully extended
flaps.”30 Dr. Cochran testified that in order for an aircraft to be stable, the neutral point
28Carducci Rebuttal Report at 40, Exhibit C, Memorandum in Support of RAC’s
Motion in Limine No. 2 (Cochran), Docket No. 312.
29Cochran Deposition at 54:16-20, Exhibit D, Memorandum in Support of RAC’s
Motion in Limine No. 2 (Cochran), Docket No. 312.
30Id. at 54:8-9.
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should be behind the center of gravity, or in other words, be “between the center of gravity
and tail . . . of the aircraft.”31 He then explained that “[a]s soon as the center of gravity is
behind the neutral point, the aircraft is unstable” and that “inputs from the pilot” such as
“lowering or raising the flaps” can move the neutral point.32 More specifically, he testified
that lowering the flaps moves the neutral point forward.33 And, Dr. Cochran agreed that the
use of full flaps at the time the accident aircraft was taking off negatively affected the pilot’s
ability to control the aircraft.34 Defendants argue that even though Dr. Cochran knew all of
this, he basically ignored the fact that the landing flaps were fully extended when the
accident aircraft was taking off, which defendants argue makes his opinions unreliable.
This is an issue about which defendants can cross examine Dr. Cochran. But it is not
an issue that makes his opinions inadmissible.
Defendants next argue that Dr. Cochran’s opinions are unreliable because he ignored
evidence that the pilot did not conduct an actual weight and balance prior to take off. At his
deposition, Dr. Cochran was asked if he had been provided any information that would
indicate or suggest that the pilot had performed a weight and balance, and Dr. Cochran
testified that he did not recall any such information but he “assumed” that the pilot had
31Id. at 153:2-6.
32Id. at 153:11-154:1.
33Id. at 154:2-4.
34Id. at 172:12-17.
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performed some kind of weight and balance because “an experience pilot would want to do
a weight and balance just to make sure that he would be able to fly the airplane. . . .”35 But
defendants contend that there is evidence that the pilot did not do a weight and balance.
They offer an NTSB witness statement from Merrill McGahan, who had brought the cargo
that was loaded on the accident aircraft out to the airport, in which McGahan stated that he
and the pilot did not weigh the cargo but simply estimated that it weighed 300 pounds.36
Defendants thus insist that Dr. Cochran’s assumption as to what the pilot did on the day of
the accident is baseless. And they argue that this is significant because others have
concluded that the accident was caused, in part, because the aircraft was improperly loaded.
There are questions of fact as to whether the pilot performed a weight and balance
calculation on the day of the accident. McGahan’s statements that they did not weigh the
cargo is not conclusive proof that the pilot did not do a weight and balance calculation prior
to accident flight.
Defendants next argue that any causation opinions from Dr. Cochran should be
excluded. Defendants contend that Dr. Cochran opines that they should have determined the
effects of the modifications on the neutral point and that the aft center of gravity limit in a
DHC-3 modified with a Texas Turbine conversion should have been 3.12 inches forward of
35Id. at 78:1-19.
36Exhibit G, Memorandum in Support of RAC’s Motion in Limine No. 2 (Cochran),
Docket No. 312. McGahan confirmed this information at his deposition. Exhibit F,
Memorandum in Support of RAC’s Motion in Limine No. 2 (Cochran), Docket No. 312.
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the authorized 152.2. But, defendants argue that Dr. Cochran did not explain in his report
how the alleged failure to conduct flight tests or the possibility of a more forward aft center
of gravity limit caused the accident. And, defendants point out that the NTSB’s Weight and
Balance Study found it likely that the accident aircraft was loaded 5.58 inches “past the aft
CG envelope limits of 152.2.”37 In other words, according to defense expert Mark Madden,
“the accident airplane was loaded 34% aft of the aft CG limit. . . .”38 Defendants argue that
this makes Dr. Cochran’s causation opinion irrelevant because under either his theory or the
allowable limit, the accident aircraft was loaded too far aft.
Dr. Cochran’s causation opinions tend to establish why the crash occurred.
Defendants may attack these opinions on cross-examination. But, Dr. Cochran’s causation
opinions are not irrelevant.
As a final matter, defendants bring up the question of a Daubert hearing. If the court
is inclined to deny their motions to exclude Dr. Cochran’s testimony, then they request a
Daubert hearing. “The district court has discretion whether to hold a Daubert hearing in
determining whether to admit expert testimony.” Millenkamp v. Davisco Foods Int’l, Inc.,
562 F.3d 971, 979 (9th Cir. 2009). “An evidentiary hearing under Daubert is not required
where the parties’ ‘briefing on [the expert’s] scientific expertise and proposed testimony’
37Expert Report of the Crash of DHC-3 Otter N93PC at 15, Exhibit D, Texas Turbine
Conversions, Inc.’s Motion to Exclude Testimony of Plaintiffs’ Expert John Cochran, Docket
No. 268.
38Id. at 16.
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provides an ‘adequate record from which the court could make its ruling’ as to admissibility.”
In re: Yosemite Nat’l Park Hantavirus Litig., Case No. 14-md-02532-MMC, 2018 WL
1033307, at *3 (N.D. Cal. Feb. 23, 2018) (quoting Millenkamp, 562 F.3d at 979). A
Daubert hearing is not necessary in this instance. The parties’ extensive briefing provided
an adequate record for the court to evaluate whether Dr. Cochran’s opinions and testimony
were admissible pursuant to Rule 702.
Conclusion
Defendants’ motions in limine to exclude Dr. Cochran’s testimony39 are denied.
DATED at Anchorage, Alaska, this 22nd day of April, 2020.
/s/ H. Russel Holland
United States District Judge
39Docket Nos. 268 and 311.
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